\documentclass[twoside]{article}
\usepackage{fleqn,espcrc2,epsf}
%\documentstyle[twoside,fleqn,espcrc2]{article}
\usepackage{graphicx}
\usepackage{epsfig}
\usepackage[figuresright]{rotating}

%\documentstyle[epsf,iopconf1]{article}
%\documentstyle{article}
%\documentstyle[sprocl,epsf]{article}

\newcommand{\be}[1]{\begin{equation} \label{(#1)}}
\newcommand{\ee}{\end{equation}}
\newcommand{\ba}[1]{\begin{eqnarray} \label{(#1)}}
\newcommand{\ea}{\end{eqnarray}}
\newcommand{\nn}{\nonumber}
\newcommand{\rf}[1]{(\ref{(#1)})}

\newcommand{\ttbs}{\char'134}
\newcommand{\AmS}{{\protect\the\textfont2
  A\kern-.1667em\lower.5ex\hbox{M}\kern-.125emS}}

%
%\def \KK {H.V.~Klapdor-Kleingrothaus}
\def \znbb {$0\nu\beta\beta$}
\def \tnbb {$2\nu\beta\beta$}
\def \Rpv{R_{P} \hspace{-0.9em}/\;\:}%\hspace{0.8em}}
\def\rp{$R_p \hspace{-1em}/\;\:$}
\def \emass {\langle m_{\nu} \rangle}
\font\eightrm=cmr8

%\input{psfig}

%\bibliographystyle{unsrt} %for BibTeX - sorted numerical labels by
                          %order of first citation.

%\arraycolsep1.5pt

% A useful Journal macro
\def\Journal#1#2#3#4{{#1} {\bf #2}, #3 (#4)}

% Some useful journal names
\def\NCA{\em Nuovo Cimento}
\def\NIM{\em Nucl. Instrum. Methods}
\def\NIMA{{\em Nucl. Instrum. Methods} {\bf A}}
\def\NPB{{\em Nucl. Phys.} {\bf B}}
\def\PLB{{\em Phys. Lett.} {\bf  B}}
\def\PRL{\em Phys. Rev. Lett.}
\def\PRD{{\em Phys. Rev.} {\bf D}}
\def\ZPC{{\em Z. Phys.} {\bf C}}

% Some other macros used in the sample text
\def\st{\scriptstyle}
\def\sst{\scriptscriptstyle}
\def\mco{\multicolumn}
\def\epp{\epsilon^{\prime}}
\def\vep{\varepsilon}
\def\ra{\rightarrow}
\def\ppg{\pi^+\pi^-\gamma}
\def\vp{{\bf p}}
\def\ko{K^0}
\def\kb{\bar{K^0}}
\def\al{\alpha}
\def\ab{\bar{\alpha}}
\def\be{\begin{equation}}
\def\ee{\end{equation}}
\def\bea{\begin{eqnarray}}
\def\eea{\end{eqnarray}}
\def\CPbar{\hbox{{\rm CP}\hskip-1.80em{/}}}%temp replacemt due to no font
\def \KK {H.V.~Klapdor-Kleingrothaus}
\hyphenation{author another created financial paper re-commend-ed Post-Script}

\title{Neutrino Mass from Laboratory:\\
Contribution of Double Beta Decay to the Neutrino Mass Matrix}


\author{H.V. Klapdor--Kleingrothaus
\address{Max--Planck--Institut f\"ur Kernphysik, 
P.O.Box 10 39 80, D--69029 Heidelberg, Germany\\
Spokesman HEIDELBERG-MOSCOW and GENIUS Collaborations\\
e-mail:klapdor@gustav.mpi-hd.mpg.de, home page: 
http://mpi-hd.mpg.de.non$\_$acc/}
}

\begin{document}

\begin{abstract}Double beta decay is indispensable to solve the question 
	of the neutrino mass matrix together with $\nu$ oscillation 
	experiments. 
	The most sensitive experiment - since eight years the 
	HEIDELBERG-MOSCOW experiment in Gran-Sasso - already now, with the 
	experimental limit of $\langle m_\nu \rangle < 0.26$ eV practically 
	excludes 
	degenerate $\nu$ mass scenarios allowing neutrinos as hot dark 
	matter in the universe for the smallangle MSW solution of the solar 
	neutrino problem. It probes cosmological models including hot 
	dark matter already now on the level of future satellite experiments 
	MAP and PLANCK. It further probes many topics of beyond SM physics 
	at the TeV scale. Future experiments should 
	give access to the multi-TeV range and complement on many ways 
	the search for new physics at future colliders like LHC and NLC. 
	For neutrino physics some of them (GENIUS) will allow to test 
	almost {\it all} neutrino mass scenarios 
	allowed by the present neutrino oscillation experiments.

	
\vspace{1pc}
\end{abstract}

\maketitle
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Sect. 1%%%%%%%%%%%%%%%%%%%%%

\section{Introduction}

	Recently atmospheric and solar neutrino oscillation experiments 
	have shown that neutrinos are massive. This is the first 
	indication of beyond standard model physics. The absolute 
	neutrino mass scale is, however, still unknown, 
	and only neutrino oscillations and neutrinoless double beta decay 
	{\it together} can solve this problem (see, e.g. 
\cite{KKPS,KKP,KK60Y}).

	In this paper we will discuss the contribution, that can be 
	given by present and future $0\nu\beta\beta$ experiments to this 
	important question of particle physics. We shall, in section 2, 
	discuss the expectations for the observable of neutrinoless double 
	beta decay, the effective neutrino mass $\langle m_\nu \rangle$, 
	from the most recent $\nu$ oscillation experiments, 
	which gives us the required sensitivity for future $0\nu\beta\beta$ 
	experiments. In section 3 we shall discuss the present status 
	and future potential of $0\nu\beta\beta$ experiments. 
	It will be shown, that if by exploiting the potential of 
	$0\nu\beta\beta$ decay to its ultimate experimental limit, it will 
	be possible to test practically 
	{\it all} neutrino mass scenarios allowed by the present neutrino 
	oscillation experiments (except for one, the hierarchical 
	LOW solution). 

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Sect. 2 %%%%%%%%%%%%%%%%%%%%%

\section{Allowed ranges of $\langle m \rangle$ by $\nu$ oscillation 
experiments}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	After the recent results from Superkamiokande (e.g. see 
\cite{Gonz00}), the prospects for a positive signal in 
	$0\nu\beta\beta$ decay have become more promising.
	The observable of double beta decay  
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Eq. 1%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\be{}
$\langle m \rangle = |\sum U_{ei}^2 m_i| = 
|m^{(1)}_{ee}| + e^{i\phi_{2}} |m_{ee}^{(2)}|
+  e^{i\phi_{3}} |m_{ee}^{(3)}|$
%\label{M}
%\ee
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Eq. 1%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	with $U_{ei}$ denoting elements of the neutrino mixing matrix, 
	$m_i$ neutrino mass eigenstates, and $\phi_i$ relative 
	Majorana CP phases, can be written in terms of oscillation 
	parameters 
\cite{KKPS,KKP}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Eq. 2,3,4%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\ba{  }
\be{}
|m^{(1)}_{ee}|  ~=~  |U_{e1}|^2 m_1, 
\ee
\be{}
|m^{(2)}_{ee}|~=~|U_{e2}|^2 \sqrt{\Delta m^2_{21} + m_1^2},
\ee
\be{}
|m^{(3)}_{ee}|~=~|U_{e3}|^2\sqrt{\Delta m^2_{32}+ \Delta m^2_{21} + m_1^2}.
\label{gg}
\ee
%\ea
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Eq. 2,3,4%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	The effective mass $\langle m \rangle$ is related with the half-life 
	for $0\nu\beta\beta$ decay via 
${(T_{1/2}^{0\nu})}^{-1} \sim {\langle m_\nu \rangle}^2$, and for the limit on 
$T_{1/2}^{0\nu}$ deducable in an experiment we have 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%Eq. 5%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\ba{  }
$T_{1/2}^{0\nu}\sim a \sqrt{\frac{M t}{\Delta E B}}$.
%\label{period}
%\ea
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Eq. 5%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	Here are a - isotopical abundance of the $\beta\beta$ emitter;  
	M - active detector mass; t - measuring time; 
	$\Delta E$ - energy resolution; B - background count rate.
	Neutrino oscillation experiments fix or restrict some of the 
	parameters in eqs. 1-3, e.g. in the case of normal hierarchy 
	solar neutrino experiments yield $\Delta m^2_{21}$, 
	$|U_{e1}|^2=\cos^2 \theta_{\odot}$ and 
	$|U_{e2}|^2=\sin^2 \theta_{\odot}$. Atmospheric neutrinos fix 
	$\Delta m^2_{32}$ and experiments like CHOOZ, looking for 
	$\nu_e$ disapperance restrict $|U_{e3}|^2$. The phases $\phi_i$ and 
	the mass of the lighest neutrino, $m_1$ are free parameters. 
	The expectations for $\langle m \rangle$ from oscillation 
	experiments in different neutrino mass scenarios have been 
	carefully analyzed in 
\cite{KKPS,KKP}.

%%%%%%%%%%%%%%%% Fig. neutrino mass hierarchy%%%%%%%%%%%%%%%%%%%%%%%%%%
\vspace{-.7cm}
\begin{figure}[htb]
\vspace{9pt}
\centering{
\includegraphics[width=0.45\textwidth]{smi1.eps}}
\vspace{-.7cm}
\caption[]{Neutrino masses and mixings in the scheme with mass hierarchy. 
	Coloured bars correspond to flavor 
	admixtures in the mass eigenstates $\nu_1$, $\nu_2$, $\nu_3$. 
	The quantity $\langle m \rangle$ is determined by the dark blue
	 bars denoting the admixture of the electron neutrino $U_{ei}$.
\label{smi1}}
\end{figure}

%%%%%%%%%%%%%%%% end Fig. NMH %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%% Hierarchical spectrum%%%%%%%%%%%%%%%%%%%%%%%
\vspace{-.7cm}
\subsection{Hierarchical spectrum ($m_1\ll m_2\ll m_3$)}
	
	In hierarchical spectra (Fig. \ref{smi1}), motivated by analogies 
	with the quark sector and the simplest 
	see-saw models, the main contribution comes from $m_2$ or $m_3$. 
	For the large mixing angle (LMA) MSW solution which is favored 
	at present for the solar neutrino problem (see 
\cite{Suz-Neutr2000}), the contribution of $m_2$ becomes dominant 
	in the expression for $\langle m \rangle$, and 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Eq. 6%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\be{}
\langle m \rangle \simeq m_{ee}^{(2)}= 
\frac{\tan^2 \theta}{1+ \tan^2 \theta} \sqrt{\Delta m_{\odot}^2}.
\ee
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Eq. 6%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	In the region allowed at 90\% c.l. by Superkamiokande according to 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Eq. 7%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\cite{Gonz00} the prediction for $\langle m \rangle$ becomes 
\be{}
\langle m \rangle = (1-3) \cdot 10^{-3}~{\rm eV}.
\ee
%%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Eq. 6%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
	The prediction extends to $\langle m \rangle=10^{-2}$ eV in 
	the 99\% c.l. range (Fig. \ref{dark2}).
%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Hierarchical spectrum%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%% Fig. dark 2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{figure}[!ht]
\begin{center}
\includegraphics[width=0.45\textwidth]{Dark2.ps}
%\includegraphics[width=0.45\textwidth]{dark2.ps}
\end{center}
\vspace{-.7cm}
\caption[]{
	Double beta decay observable $\langle m \rangle$ and oscillation 
	parameters 
	in the case of the MSW large mixing solution of the solar 
	neutrino deficit, where the dominant contribution to 
$\langle m \rangle$
	comes from the second state. Shown are lines 
	of constant $\langle m \rangle$, the lowest line corresponding to 
	$\langle m_\nu \rangle$ = 0.001 eV, the upper line to 0.01 eV.
	The inner and outer closed line show the regions allowed by present 
	solar neutrino experiments with 90 \% C.L. and 99 \% C.L., 
	respectively. 
	Double beta decay with sufficient sensitivity could check the LMA 
	MSW solution.
	Complementary information could be obtained
%	from double beta decay, 
	from the search for
	a day-night effect and spectral distortions 
	in future solar neutrino experiments as well as a disappearance 
	signal in KAMLAND. 
\label{dark2}}
\end{figure}

%%%%%%%%%%%%%%%% end Fig. dark 2 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%% Inverse Hierarchy%%%%%%%%%%%%%%%%%%%%%%%
\vspace{-.9cm}
\subsection{Inverse Hierarchy ($m_3 \approx  m_2 \gg m_1$)}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	In inverse hierarchy scenarios (Fig. \ref{smi2}) the heaviest 
	state with 
	mass $m_3$ is mainly the electron neutrino, its mass being 
	determined by atmospheric neutrinos,  
$m_3 \simeq \sqrt{\Delta m_{atm}^2}$. 
	For the LMA MSW solution one finds
\cite{KKP}
\be{}
\langle m \rangle = (1-7) \cdot 10^{-2}~{\rm eV}.
\ee 
%%%%%%%%%%%%%%%%%%%%%%%%%%%% end Inverse Hierarchical%%%%%%%%%%%%%%%%	

%%%%%%%%%%%%%%%% Fig. Invers. Hierarchy%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\vspace{-1.9cm}
\begin{figure}[htb]
\vspace{9pt}
\centering{
\includegraphics[width=0.45\textwidth]{smi3.eps}}
\vspace{-0.6cm}
\caption[]{Neutrino masses and mixings in the inverse hierarchy scenario.
\label{smi2}}
\end{figure}

%%%%%%%%%%%%%%%% end Fig. Fig. Invers. Hierarchy%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%% Degenerate Spectrum%%%%%%%%%%%%%%%%%%%%%%%
\vspace{-.1cm}
\subsection{Degenerate spectrum 
($m_1 \simeq  m_2 \simeq  m_3 \ge\sim 0.1 eV$)}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	Since the contribution of $m_3$ is strongly restricted by CHOOZ, 
	the main contributions come from $m_1$ and $m_2$, depending on 
	their admixture to the electron flavors, which is determined 
	by the solar neutrino solution. We find \cite{KKP} 
\be{}
m_{min} < \langle m \rangle < m_1~~~~with
\label{m-min}
\ee 
\ba{}
\langle m \rangle_{min} = (\cos^2 \theta_{\odot}-\sin^2 
\theta_{\odot})~m_1 \nonumber.
%      &=& \frac{1-\tan^2 \theta_{\odot}}{1+\tan^2 \theta_{\odot}}~m_1. 
\ea
%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	This leads for the LMA solution to 
$\langle m \rangle = (0.25 - 1) \cdot m_1$, the allowed range corresponding 
	to possible values of the unknown Majorana CP-phases.

	After these examples we give a summary of our analysis 
\cite{KKPS,KKP} of the $\langle m \rangle$ allowed by $\nu$ oscillation 
	experiments for the neutrino mass models in the presently 
	favored scenarios, in 
Fig. \ref{NewSm-Pfig}. 
	The size of the bars corresponds to the uncertainty in mixing 
	angles and the unknown Majorana CP-phases.

%%%%%%%%%%%%%%%% new graf. different schemes neutrino masses%%%%%%%%%%%%%%%%
%\vspace{-0.9cm}
\begin{figure}[htb]
\vspace{9pt}
\centering{
%\includegraphics[width=0.28\textwidth, angle=-90]
%{Jahr00-Sum-difSchemNeutr.ps}}
\includegraphics[width=0.5\textwidth]{cstatessum.eps}}
\vspace{-0.7cm}
\caption[]{Summary of values for $m_{ee} \equiv \langle m \rangle $ 
	expected from neutrino oscillation 
	experiments (status NEUTRINO2000), in the different 
	schemes discussed in this paper. For a more general analysis see 
\cite{KKPS}.  
	The expectations are compared with the recent neutrino mass limits 
	obtained from the HEIDELBERG-MOSCOW 
\cite{hdmo,KK-AnnRep00},
	experiment as well as the expected sensitivities for the CUORE 
\cite{cuore}
%, \cite{Fior01}
, MOON 
\cite{moon}, EXO 
\cite{exo} proposals and the 1 ton and 10 ton proposal of GENIUS 
\cite{KK-BEY97,KKPropos99}.
\label{NewSm-Pfig}}
\end{figure}

%%%%%%%%%%%%%%%% end new graf. different schemes neutrino masses%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\vspace{-0.9cm}
\section{Status and Future of $\beta\beta$ Experiments}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%

	The status of present double beta experiments is shown in 
Fig. 1 of 
\cite{KK1-NOW00} and extensively discussed in 
\cite{KK60Y}. The HEIDELBERG-MOSCOW experiment using the largest source 
strength of 11 kg of enriched $^{76}{Ge}$ in form of five HP Ge-detectors 
	in the Gran-Sasso underground laboratory 
\cite{KK60Y}, yields after a time of 37.2 kg y of measurement 
(Fig. \ref{Spectr2000}) 
	a half-life limit of \cite{KK-AnnRep00}

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\vspace{.2cm}
$T_{1/2}^{0\nu} > 2.1 (3.5) \cdot {10}^{25}~ y, ~~~~ 90\% (68\%) c.l.$

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\vspace{.2cm}
\noindent
and a limit for the effective neutrino mass of 

$\langle m \rangle < 0.34 (0.26) ~eV, ~~~~ 90\% (68\%) c.l.. $

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%%%%%%%%%%%%%%% new graf. different schemes neutrino masses%%%%%%%%%%%%%%%%
%\vspace{-0.3cm}
\begin{figure}[htb]
\vspace{9pt}
\centering{
\includegraphics[width=0.35\textwidth, angle=-90]{Spectr-37-24kgy.ps}}
%\includegraphics[width=0.35\textwidth, angle=-90]{Spectrum2000.ps}}
\vspace{-0.7cm}
\caption[]{HEIDELBERG-MOSCOW experiment: energy spectrum in the range 
	between 2000 keV and 2080 keV, where the peak from neutrinoless 
	double beta decay is expected. The open histogram denoteds the 
	overal sum spectrum without PSA after 55.9 kg y of measurement 
	(since 1992). The filled histogram corresponds to the SSe data 
	after 37.2 kg y. Shown are also the excluded (90\%) peak areas 
	from the two spectra.} 
\label{Spectr2000}
\end{figure}

%%%%%%%%%%%%%%%% end new graf. different schemes neutrino masses%%%%%%%%%%%%%%

\vspace{0.1cm}
	This sensitivity just starts to probe some (degenerate) neutrino 
	mass models. In degenerate models from the experimental limit on 
	$\langle m \rangle$ we can conclude on upper bound on the mass 
	scale of the 
	heaviest neutrino. For the LMA solar solution we obtain from eq. 
(\ref{m-min}) $m_{1,2,3} < 1.1 eV$ implying $\sum m_i < 3.2 eV$.
	This first number is sharper than what has recently been deduced 
	from single beta decay of tritium ($m < $ 2.2 eV 
\cite{WeinLob-Neutr2000}), 
	and the second is sharper than the limit of 
	$\sum m_i <$ 5.5. eV still compatible with most recent fits of 
	Cosmic Microwave Background Radiation and Large Scale Structure 
	data (see, e.g. 
\cite).
	The result has found a large resonance, and it has 
	been shown that it excludes for example the small angle 
	MSW solution of the solar neutrino problem in degenerate scenarios, 
	if neutrinos are considered as hot dark matter in the universe 
\cite{Glash,Min97,Yas-Bey00,Ell99}. 
Fig. \ref{osc-param} shows that the present 
	sensitivity probes cosmological 
	models including hot dark matter already now on a level of future 
	satellite experiments MAP and PLANCK. The HEIDELBERG-MOSCOW 
	experiment yields the by far sharpest limits worldwide. 
%\cite{KKAnnRep99-00}. 
	If future searches will show that $\langle m \rangle >$ 0.1 eV, than 
	the three-$\nu$ mass schemes, which will survive, are those with 
	$\nu$ mass degeneracy or 4-neutrino schemes with inverse mass 
	hierarchy ( 
Fig. \ref{NewSm-Pfig} and \cite{KKPS}).
	It has been discussed in detail earlier (see e.g. 
\cite{KK-BEY97,KK99nu98,KK1-NOW00} 
\cite{KK60Y}), that of present generation experiments no one 
	(including NEMO-III,
%, CUORICINO,
	...) has a potential to probe 
	$\langle m_\nu \rangle$ below the present HEIDELBERG-MOSCOW level. 

	A possibility to probe $\langle m \rangle$ down to $\sim 0.1$ eV 
	(90\% c.l.) exists with the GENIUS Test Facility 
\cite{KKAnnRep99-00} 
	which should reduce the background by a factor of 30  compared to 
	the HEIDELBERG-MOSCOW experiment, and thus 
	could reach a half-life limit of $1.5 \cdot {10}^{26}$ y.

	To extend the sensitivity of $\beta\beta$ experiments below this 
	limit requires completely new experimental approaches, as discussed 
	extensively in 
\cite{KK-BEY97,KKPropos99,KK99nu98}, and in another contribution to this 
	conference 
\cite{KK1-NOW00}.

	Fig. \ref{NewSm-Pfig} shows that an improvement of the sensitivity 
	down to 
	$\langle m \rangle \sim {10}^{-3}$ eV is required to probe all 
	neutrino mass scenarios allowed by present neutrino oscillation 
	experiments. With this result of $\nu$ oscillation experiments nature 
	seems to be generous to us since such a sensitivity seems to be 
	achievable in future $\beta\beta$ experiment, if this method is 
	exploited to its ultimate limit (see \cite{KK1-NOW00}).

%%%%%%%%%%%%%%%% Fig. DBD observable%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%\vspace{-1.1cm}
\begin{figure}[htb]
\vspace{9pt}
\centering{
\includegraphics[width=0.38\textwidth,angle=-90]{Dark3.ps}}
%\includegraphics[width=0.45\textwidth]{dark3.ps}}
\vspace{-.5cm}
\caption[]{Double beta decay observable $\langle m \rangle$ and 
	oscillations parameters:
	The case for degenerate neutrinos. Plotted on the axes are 
	the overall scale of neutrino masses $m_0$
	and the mixing $\tan^2 2 \theta_{12}$.
%Allowed values for $\langle m \rangle$ for a given $m_0$ correspond to the 
%regions 
%between $m_0$ and the corresponding curved line. 
	Also shown is a cosmological bound deduced from a fit of CMB and 
	large scale structure 
\cite{cmb} 
%informations which could be obtained from 
%	cosmological fits (see text) 
	and the expected 
	sensitivity of the satellite experiments MAP and Planck. 
%A value of $\langle m \rangle = 0.1$ eV 
	The present limit from tritium $\beta$ decay of 2.2 eV 
\cite{Weinh2000}
	would lie near the top of the figure. 
	The range of $\langle m \rangle$  investigated at present by the 
	HEIDELBERG-MOSCOW experiment is, in the case of small solar neutrino
	mixing already in 
	the range to be explored by MAP and Planck \protect{\cite{cmb}.}
\label{osc-param}}
\end{figure}

%%%%%%%%%%%%%%%% end Fig. DBD observable%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%%%%%%%%%%%%%%%% Fig. neutrino mass and mixings %%%%%%%%%%%%%%%%%%%%%%%%%%
%\begin{figure}[htb]
%\vspace{9pt}
%\centering{
%\includegraphics[width=0.45\textwidth]{smi2.eps}}
%\caption[]{Neutrino masses and mixings in the degenerate scheme.
%\label{smi2}}
%\end{figure}
%%%%%%%%%%%%%%%% end Fig. NMMinDeg-sch %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%



%%%%%%%%%%%%%%%% Fig. %%%%%%%%%%%%%%%%%%%%%%%%%%
%\begin{figure}[htb]
%\vspace{9pt}
%\centering{
%\includegraphics*[width=80mm, height=55mm]{sumspec_betabeta.eps}} 
%%for GENIUS article
%\caption{Simulated cosmogenic background during detector production. 
%	Assumptions: 30 days exposure of material before processing, 
%	1 d activation after zone refining, 3 y deactivation underground 
%	(see \cite{LowNu2}).}
%\end{figure}

%%%%%%%%%%%%%%%% end Fig.  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\begin{thebibliography}{9}

\bibitem{KKPS} H.V. Klapdor-Kleingrothaus, H. P\"as and A.Yu. Smirnov,
	Preprint: {\it hep-ph/}{\, (2000) and 
	in {\it Phys. Rev.} {\bf D} (2000).

\bibitem{KKP} H.V. Klapdor-Kleingrothaus, H. P\"as and A.Yu. Smirnov, 
	in Proc. of DARK2000, 
	Heidelberg, 10-15 July, 2000, Germany, 
	ed H. V. Klapdor-Kleingrothaus, Springer, Heidelberg (2001).	

\bibitem{KK60Y} \KK, {\sf "60 Years of Double Beta Decay"},
	{\it World Scientific, Singapore} (2001) 1253p.

\bibitem{KKPcomm} \KK ~and H. P\"as, Preprint: {\it physics/}{\ 
	and {\it Comm. in Nucl. and Part. Phys.} (2000).

\bibitem{LowNu2} \KK~, in Proc. International Workshop 
%on Low Energy Solar Neutrinos. 
	LowNu2, December 4 and 5 (2000) Tokyo, Japan, 
	ed: Y. Suzuki, {\it World Scientific, Singapore} (2001).

\bibitem{Bau-KK} L. Baudis and H.V. Klapdor-Kleingrothaus, 
	{\it Eur. Phys. J.} {\bf A 5} (1999) 441-443. 

\bibitem{hdmo}
H.V. Klapdor-Kleingrothaus et al., to be publ. 2000 and
$http://www.mpi-hd.mpg.de/non_acc/main.html$

\bibitem{cuore}
E. Fiorini et al., {\it Phys. Rep.} {\bf 307} (1998) 309. 

%\bibitem{Fior01}
%E. Fiorini, priv. communications, (Jan. 2000).
%
\bibitem{moon}
H. Ejiri et al., {\it nucl-ex/}{\.

\bibitem{exo}
M. Danilov et al., {\it Phys. Lett.} {\bf B 480} (2000) 12-18.

\bibitem{KK-BEY97} \KK ~in Proceedings of BEYOND'97
%the First International Conference on 
%	Particle Physics Beyond the Standard Model, Castle Ringberg, 
	Germany, 8-14 June 1997, edited by  H.V. Klapdor-Kleingrothaus 
	and H.P\"as, {\it IOP Bristol} (1998) 485-531 and
	{\it Int. J. Mod. Phys.} {\bf A 13} (1998) 3953, and
	{\it J. Phys.} {\bf G 24} (1998) 483 - 516. 

\bibitem{KKPropos99} H.V. Klapdor-Kleingrothaus et al. 
%L. Baudis, G.~Heusser, B.~Majorovits and H.~P\"as, 
%GENIUS - a Supersensitive Germanium
%  	Detector System for Rare Events, Proposal, 
	{\it MPI-Report} {\bf MPI-H-V26-1999} 
	and Preprint: {\it hep-ph/}{\ and in Proceedings of 
%the 
%	Second International Conference on Particle Physics Beyond the 
%	Standard Model 
	BEYOND'99, Castle Ringberg, Germany, 6-12 June 
	1999, edited by \KK~ and I.V. Krivosheina, {\it IOP Bristol}, 
	(2000) 915 - 1014. 

\bibitem{KK99nu98} \KK, ~in Proc. of 
%18th International Conference on Neutrino Physics and Astrophysics 
	(NEUTRINO 98), Takayama, Japan, 
	4-9 Jun 1998, (eds) Y. Suzuki et al. 
	{\it Nucl. Phys. Proc. Suppl.} {\bf 77} (1999) 357 - 368.

%\bibitem{KK99WEIN98} \KK, ~in Proc. of WEIN'98, "Physics Beyond the 
%	Standard Model", Proceedings of the Fifth International WEIN 
%	Conference, P. Herczeg, C.M. Hoffman and \KK (Editors),  
%	{\it World Scientific, Singapore} (1999) 275 -- 311.
%
%\bibitem{KK-TR98} H.V. Klapdor-Kleingrothaus, in Proc of International 
%	Symposium on Lepton and Baryon Number Violation, Trento, Italy, 
%	20-25 April, 1998, ed H.V. Klapdor-Kleingrothaus and 
%	I.V. Krivosheina, {\it IOP, Bristol}, (1999) 251-301 and 
%	Preprint: {\it hep-ex/}{\, and 
%	{\it Int. J. Mod. Phys.} {\bf A13} (1998) 3953 - 3992.
%
\bibitem{cmb} R.E. Lopez, ;
	J.R. Primack, M.A.K. Gross, ;
	J.R. Primack, ;
	J. Einasto, in Proc. of DARK2000, Heidelberg, Germany, July 10-15, 
	2000, Ed. H.V. Klapdor-Kleingrothaus, 
	{\it Springer, Heidelberg}, (2001).

\bibitem{Suz-Neutr2000} Y. Suzuki in Proc. of NEUTRINO2000, Sudbury, Canada, 
	June 2000, ed. A.B. McDonald et al. (2001).

\bibitem{Gonz00} M.C. Gonzalez-Garcia, M. Maltoni, C. Pe\~na-Garay, 
	J.W.F. Valle, {\it hep-ph/}{\, 
	{\it Phys. Rev.} {\bf D63} (2001) 033005.

\bibitem{KK-AnnRep00} H.V. Klapdor-Kleingrothaus et al., 
	{\it Annual Report Gran Sasso 2000} (2001). 

\bibitem{KKAnnRep99-00} H.V. Klapdor-Kleingrothaus et al., MPI Heidelberg, 
	{\it Annual Report 1999-2000} (2001). 

%\bibitem{mass01eV} HEIDELBERG-MOSCOW Coll., {\it Phys. Rev. Lett.} {\bf 83} 
%	(1999) 41 - 44.
%
\bibitem{KK1-NOW00} Talk on this conference H.V.Klapdor-Kleingrothaus 
	``GENIUS - A New Facility of Non-Accelerator Particle Physics''.

\bibitem{KK-NOON} H.V. Klapdor-Kleingrothaus in Proc. of NOON2000,  
%	International Workshop on ``Neutrino Oscillations and their Origin'', 
	Tokyo, Dec. 2000, World Scientific, Singapore (2001).

\bibitem{Glash} H. Georgi and S.L. Glashow, {Phys. Rev.} {\it D 61} (2000) 
	097301.

\bibitem{Min97} H. Minakata and O. Yasuda, {\it Phys. Rev.} {\it D 56} (1997) 
	1692 and Minakata, {\it hep-ph/} {\.

\bibitem{Yas-Bey00} O. Yasuda in Proc. of Beyond the Desert'99, ed. 
	by H.V. Klapdor-Kleingrothaus and I.V. Krivosheina, {\it IOP Bristol} 
	(2000) 223.

\bibitem{Ell99} J. Ellis and S. Lola, {\it Phys. Lett.} {\bf B 458} (1999) 
	310 and Preprint: {\it hep-ph/}{\.

\bibitem{WeinLob-Neutr2000} C. Weinheimer in Proc, of NEUTRINO2000, Sudbury, 
	Canada, June 16 - June 21 (2000).

\bibitem M. Tegmark, M. Zaldarriaga and A.J.S. Hamilton, 
	Preprint: {\it hep-ph/} {\.

\bibitem{Weinh2000} Ch. Weinheimer in Proc. of NEUTRINO2000, Sudbury, Canada, 
	June 2000, ed. A.B. McDonald et al. (2001). 
 
\end{thebibliography}

\end{document}
%%%%%%%%%% espcrc2.tex %%%%%%%%%%
%
% $Id: espcrc2.tex 1.1 1999/07/26 10:28:22 Simon Exp spepping $
%
\documentclass[twoside]{article}
\usepackage{fleqn,espcrc2}

% change this to the following line for use with LaTeX2.09
% \documentstyle[twoside,fleqn,espcrc2]{article}

% if you want to include PostScript figures
\usepackage{graphicx}
% if you have landscape tables
\usepackage[figuresright]{rotating}

% put your own definitions here:
%   \newcommand{\cZ}{\cal{Z}}
%   \newtheorem{def}{Definition}[section]
%   ...
\newcommand{\ttbs}{\char'134}
\newcommand{\AmS}{{\protect\the\textfont2
  A\kern-.1667em\lower.5ex\hbox{M}\kern-.125emS}}

% add words to TeX's hyphenation exception list
\hyphenation{author another created financial paper re-commend-ed Post-Script}

% declarations for front matter
\title{Elsevier instructions for the preparation of a
       2-column format camera-ready paper in \LaTeX}

\author{P. de Groot\address{Mathematics and Computer Science Division, 
        Elsevier Science Publishers B.V., \\ 
        P.O. Box 103, 1000 AC Amsterdam, The Netherlands}%
        \thanks{Footnotes should appear on the first page only to
                indicate your present address (if different from your
                normal address), research grant, sponsoring agency, etc.
                These are obtained with the {\tt\ttbs thanks} command.}
        and 
        X.-Y. Wang\address{Economics Department, University of Winchester, \\
        2 Finch Road, Winchester, Hampshire P3L T19, United Kingdom}}
       
\begin{document}

\begin{abstract}
These pages provide you with an example of the layout and style for
100\% reproduction which we wish you to adopt during the preparation of
your paper. This is the output from the \LaTeX{} document class you
requested.
\vspace{1pc}
\end{abstract}

% typeset front matter (including abstract)
\maketitle

\section{FORMAT}

Text should be produced within the dimensions shown on these pages:
each column 7.5 cm wide with 1 cm middle margin, total width of 16 cm
and a maximum length of 20.2 cm on first pages and 21 cm on second and
following pages. The \LaTeX{} document class uses the maximal stipulated
length apart from the following two exceptions (i) \LaTeX{} does not
begin a new section directly at the bottom of a page, but transfers the
heading to the top of the next page; (ii) \LaTeX{} never (well, hardly
ever) exceeds the length of the text area in order to complete a
section of text or a paragraph. Here are some references:
\cite{Scho70,Mazu84}.

\subsection{Spacing}

We normally recommend the use of 1.0 (single) line spacing. However,
when typing complicated mathematical text \LaTeX{} automatically
increases the space between text lines in order to prevent sub- and
superscript fonts overlapping one another and making your printed
matter illegible.

\subsection{Fonts}

These instructions have been produced using a 10 point Computer Modern
Roman. Other recommended fonts are 10 point Times Roman, New Century
Schoolbook, Bookman Light and Palatino.

\section{PRINTOUT}

The most suitable printer is a laser printer. A dot matrix printer
should only be used if it possesses an 18 or 24 pin printhead
(``letter-quality'').

The printout submitted should be an original; a photocopy is not
acceptable. Please make use of good quality plain white A4 (or US
Letter) paper size. {\em The dimensions shown here should be strictly
adhered to: do not make changes to these dimensions, which are
determined by the document class}. The document class leaves at least
3~cm at the top of the page before the head, which contains the page
number.

Printers sometimes produce text which contains light and dark streaks,
or has considerable lighting variation either between left-hand and
right-hand margins or between text heads and bottoms. To achieve
optimal reproduction quality, the contrast of text lettering must be
uniform, sharp and dark over the whole page and throughout the article.

If corrections are made to the text, print completely new replacement
pages. The contrast on these pages should be consistent with the rest
of the paper as should text dimensions and font sizes.

\section{TABLES AND ILLUSTRATIONS}

Tables should be made with \LaTeX; illustrations should be originals or
sharp prints. They should be arranged throughout the text and
preferably be included {\em on the same page as they are first
discussed}. They should have a self-contained caption and be positioned
in flush-left alignment with the text margin within the column. If they
do not fit into one column they may be placed across both columns
(using \verb-\begin{table*}- or \verb-\begin{figure*}- so that they
appear at the top of a page).

\subsection{Tables}

Tables should be presented in the form shown in
Table~\ref{table:1}.  Their layout should be consistent
throughout.

\begin{table*}[htb]
\caption{The next-to-leading order (NLO) results
{\em without} the pion field.}
\label{table:1}
\newcommand{\m}{\hphantom{$-$}}
\newcommand{\cc}[1]{\multicolumn{1}{c}{#1}}
\renewcommand{\tabcolsep}{2pc} % enlarge column spacing
\renewcommand{\arraystretch}{1.2} % enlarge line spacing
\begin{tabular}{@{}lllll}
\hline
$\Lambda$ (MeV)           & \cc{$140$} & \cc{$150$} & \cc{$175$} & \cc{$200$} \\
\hline
$r_d$ (fm)                & \m1.973 & \m1.972 & \m1.974 & \m1.978 \\
$Q_d$ ($\mbox{fm}^2$)     & \m0.259 & \m0.268 & \m0.287 & \m0.302 \\
$P_D$ (\%)                & \m2.32  & \m2.83  & \m4.34  & \m6.14  \\
$\mu_d$                   & \m0.867 & \m0.864 & \m0.855 & \m0.845 \\
$\mathcal{M}_{\mathrm{M1}}$ (fm)   & \m3.995 & \m3.989 & \m3.973 & \m3.955 \\
$\mathcal{M}_{\mathrm{GT}}$ (fm)   & \m4.887 & \m4.881 & \m4.864 & \m4.846 \\
$\delta_{\mathrm{1B}}^{\mathrm{VP}}$ (\%)   
                          & $-0.45$ & $-0.45$ & $-0.45$ & $-0.45$ \\
$\delta_{\mathrm{1B}}^{\mathrm{C2:C}}$ (\%) 
                          & \m0.03  & \m0.03  & \m0.03  & \m0.03  \\
$\delta_{\mathrm{1B}}^{\mathrm{C2:N}}$ (\%) 
                          & $-0.19$ & $-0.19$ & $-0.18$ & $-0.15$ \\
\hline
\end{tabular}\\[2pt]
The experimental values are given in ref. \cite{Eato75}.
\end{table*}

\begin{sidewaystable}
\caption{The next-to-leading order (NLO) results
{\em without} the pion field.}
\label{table:2}
\newcommand{\m}{\hphantom{$-$}}
\newcommand{\cc}[1]{\multicolumn{1}{c}{#1}}
\renewcommand{\arraystretch}{1.2} % enlarge line spacing
\begin{tabular*}{\textheight}{@{\extracolsep{\fill}}lllllllllllll}
\hline
& $\Lambda$ (MeV) & \cc{$140$} & \cc{$150$} & \cc{$175$} & \cc{$200$} & \cc{$225$} & \cc{$250$} &
\cc{Exp.} & \cc{$v_{18}$~\cite{v18}} &  \\
\hline
%b
 & $r_d$ (fm)                        & \m1.973 & \m1.972 & \m1.974 & \m1.978 & \m1.983 & \m1.987 & 1.966(7) & \m1.967 & \\[2pt]
 & $Q_d$ ($\mbox{fm}^2$)             & \m0.259 & \m0.268 & \m0.287 & \m0.302 & \m0.312 & \m0.319 & 0.286    & \m0.270 & \\[2pt]
 & $P_D$ (\%)                        & \m2.32  & \m2.83  & \m4.34  & \m6.14  & \m8.09  & \m9.90  & $-$      & \m5.76  & \\[2pt]
 & $\mu_d$                           & \m0.867 & \m0.864 & \m0.855 & \m0.845 & \m0.834 & \m0.823 & 0.8574   & \m0.847 & \\[5pt]
 & $\mathcal{M}_{\mathrm{M1}}$ (fm)             & \m3.995 & \m3.989 & \m3.973 & \m3.955 & \m3.936 & \m3.918 & $-$      & \m3.979 & \\[5pt]
 & $\mathcal{M}_{\mathrm{GT}}$ (fm)             & \m4.887 & \m4.881 & \m4.864 & \m4.846 & \m4.827 & \m4.810 & $-$      & \m4.859 & \\[2pt]
 & $\delta_{\mathrm{1B}}^{\mathrm{VP}}$ (\%)   & $-0.45$ & $-0.45$ & $-0.45$ & $-0.45$ & $-0.45$ & $-0.44$ & $-$      & $-0.45$ & \\[2pt]
 & $\delta_{\mathrm{1B}}^{\mathrm{C2:C}}$ (\%) & \m0.03  & \m0.03  & \m0.03  & \m0.03  & \m0.03  & \m0.03  & $-$      & \m0.03  & \\[2pt]
 & $\delta_{\mathrm{1B}}^{\mathrm{C2:N}}$ (\%) & $-0.19$ & $-0.19$ & $-0.18$ & $-0.15$ & $-0.12$ & $-0.10$ & $-$      & $-0.21$ & \\
\hline
\end{tabular*}\\[2pt]
The experimental values are given in ref. \cite{Eato75}.
\end{sidewaystable}

Horizontal lines should be placed above and below table headings, above
the subheadings and at the end of the table above any notes. Vertical
lines should be avoided.

If a table is too long to fit onto one page, the table number and
headings should be repeated above the continuation of the table. For
this you have to reset the table counter with
\verb|\addtocounter{table}{-1}|. Alternatively, the table can be turned
by $90^\circ$ (`landscape mode') and spread over two consecutive pages
(first an even-numbered, then an odd-numbered one) created by means of
\verb|\begin{table}[h]| without a caption. To do this, you prepare the
table as a separate \LaTeX{} document and attach the tables to the
empty pages with a few spots of suitable glue.

\subsection{Useful table packages}

Modern \LaTeX{} comes with several packages for tables that
provide additional functionality. Below we mention a few. See
the documentation of the individual packages for more details. The
packages can be found in \LaTeX's \texttt{tools} directory.

\begin{description}
  
\item[\texttt{array}] Various extensions to \LaTeX's \texttt{array}
  and \texttt{tabular} environments.
  
\item[\texttt{longtable}] Automatically break tables over several
  pages. Put the table in the \texttt{longtable} environment instead
  of the \texttt{table} environment.
  
\item [\texttt{dcolumn}] Define your own type of column. Among others,
  this is one way to obtain alignment on the decimal point.

\item[\texttt{tabularx}] Smart column width calculation within a
  specified table width.
  
\item[\texttt{rotating}] Print a page with a wide table or figure in
  landscape orientation using the \texttt{sidewaystable} or
  \texttt{sidewaysfigure} environments, and many other rotating
  tricks. Use the package with the \texttt{figuresright} option to
  make all tables and figures rotate in clockwise. Use the starred
  form of the \texttt{sideways} environments to obtain full-width
  tables or figures in a two-column article.

\end{description}

\subsection{Line drawings}

Line drawings should be drawn in India ink on tracing paper with the
aid of a stencil or should be glossy prints of the same; computer
prepared drawings are also acceptable. They should be attached to your
manuscript page, correctly aligned, using suitable glue and {\em not
transparent tape}. When placing a figure at the top of a page, the top
of the figure should be at the same level as the bottom of the first
text line.

All notations and lettering should be no less than 2\,mm high. The use
of heavy black, bold lettering should be avoided as this will look
unpleasantly dark when printed.

\subsection{PostScript figures}

Instead of providing separate drawings or prints of the figures you
may also use PostScript files which are included into your \LaTeX{}
file and printed together with the text. Use one of the packages from
\LaTeX's \texttt{graphics} directory: \texttt{graphics},
\texttt{graphicx} or \texttt{epsfig}, with the \verb|\usepackage|
command, and then use the appropriate commands
(\verb|\includegraphics| or \verb|\epsfig|) to include your PostScript
file.

The simplest command is: \newline
\verb|\includegraphics{file}|, which inserts the
PostScript file \texttt{file} at its own size. The starred version of
this command: \newline
\verb|\includegraphics*{file}|, does the same, but clips
the figure to its bounding box.

With the \texttt{graphicx} package one may specify a series of options
as a key--value list, e.g.:
\begin{tabular}{@{}l}
\verb|\includegraphics[width=15pc]{file}|\\
\verb|\includegraphics[height=5pc]{file}|\\
\verb|\includegraphics[scale=0.6]{file}|\\
\verb|\includegraphics[angle=90,width=20pc]{file}|
\end{tabular}

See the file \texttt{grfguide}, section ``Including Graphics Files'',
of the \texttt{graphics} distribution for all options and a detailed
description.

The \texttt{epsfig} package mimicks the commands familiar from the
package with the same name in \LaTeX2.09. A PostScript file
\texttt{file} is included with the command
\verb|\psfig{file=file}|.

Grey-scale and colour photographs cannot be included in this way,
since reproduction from the printed CRC article would give
insufficient typographical quality. See the following subsections.

\begin{figure}[htb]
\vspace{9pt}
\framebox[55mm]{\rule[-21mm]{0mm}{43mm}}
\caption{Good sharp prints should be used and not (distorted) photocopies.}
\label{fig:largenenough}
\end{figure}
%
\begin{figure}[htb]
\framebox[55mm]{\rule[-21mm]{0mm}{43mm}}
\caption{Remember to keep details clear and large enough.}
\label{fig:toosmall}
\end{figure}

\subsection{Black and white photographs}

Photographs must always be sharp originals ({\em not screened
versions\/}) and rich in contrast. They will undergo the same reduction
as the text and should be pasted on your page in the same way as line
drawings.

\subsection{Colour photographs}

Sharp originals ({\em not transparencies or slides\/}) should be
submitted close to the size expected in publication. Charges for the
processing and printing of colour will be passed on to the author(s) of
the paper. As costs involved are per page, care should be taken in the
selection of size and shape so that two or more illustrations may be
fitted together on one page. Please contact the Technical Editor in the
Camera-Ready Publications Department at Elsevier for a price quotation
and layout instructions before producing your paper in its final form.

\section{EQUATIONS}

Equations should be flush-left with the text margin; \LaTeX{} ensures
that the equation is preceded and followed by one line of white space.
\LaTeX{} provides the package {\tt fleqn} to get the flush-left
effect.

\begin{equation}
H_{\alpha\beta}(\omega) = E_\alpha^{(0)}(\omega) \delta_{\alpha\beta} +
                          \langle \alpha | W_\pi | \beta \rangle 
\end{equation}

You need not put in equation numbers, since this is taken care of
automatically. The equation numbers are always consecutive and are
printed in parentheses flush with the right-hand margin of the text and
level with the last line of the equation. For multi-line equations, use
the {\tt eqnarray} environment. For complex mathematics, use the
\AmS-\LaTeX{} package.

\begin{thebibliography}{9}
\bibitem{Scho70} S. Scholes, Discuss. Faraday Soc. No. 50 (1970) 222.
\bibitem{Mazu84} O.V. Mazurin and E.A. Porai-Koshits (eds.),
                 Phase Separation in Glass, North-Holland, Amsterdam, 1984.
\bibitem{Dimi75} Y. Dimitriev and E. Kashchieva, 
                 J. Mater. Sci. 10 (1975) 1419.
\bibitem{Eato75} D.L. Eaton, Porous Glass Support Material,
                 US Patent No. 3 904 422 (1975).
\end{thebibliography}

References should be collected at the end of your paper. Do not begin
them on a new page unless this is absolutely necessary. They should be
prepared according to the sequential numeric system making sure that
all material mentioned is generally available to the reader. Use
\verb+\cite+ to refer to the entries in the bibliography so that your
accumulated list corresponds to the citations made in the text body. 

Above we have listed some references according to the
sequential numeric system \cite{Scho70,Mazu84,Dimi75,Eato75}.
\end{document}

