181 lines
4.0 KiB
TeX
181 lines
4.0 KiB
TeX
\documentclass[12pt]{article}
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\usepackage[left=2.0cm,right=2.0cm,top=2.0cm,bottom=2.0cm]{geometry}
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\usepackage[dvips]{color}
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\renewcommand{\baselinestretch}{1.0}
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%%% FONT SIZE TABLE
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% Default : 12pt
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% Huge : 25pt
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% huge : 25pt
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% LARGE : 21pt
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% Large : 17pt
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% large : 14pt
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% normalsize : 12pt
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% small : 11pt
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% footnotesize: 10pt
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% scriptsize : 8pt
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% tiny : 6pt
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\begin{document}
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\pagestyle{empty}
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\parindent=0mm
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\parskip=0mm
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% Custom macros
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\newcommand{\lagr}{\cal{L}}
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\newcommand{\mueg}{$\mu^{+} \rightarrow e^{+}\gamma$~}
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\newcommand{\meee}{$\mu \rightarrow eee$~}
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\newcommand{\muenn}{$\mu \rightarrow e \nu \overline{\nu}$~}
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\newcommand{\muenng}{$\mu \rightarrow e \nu \overline{\nu} \gamma$~}
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\newcommand{\muec}{$\mu^{-} N \rightarrow e^{-} N$~}
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\newcommand{\muecaz}{$\mu^{-} + N(A,Z) \rightarrow e^{-} + N(A,Z)$~}
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\begin{center}
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%%%
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%%% TITLE
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%%%
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%{\large\bfseries The COMET Experiment and its Background Study}
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{\large\bfseries Status of the COMET Experiment at J-PARC}
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~\\
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%%%
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%%% AUTHOR(S)
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%%%
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\underline{Nam Hoai Tran}, on behalf of the COMET Collaboration
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~\\
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%%%
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%%% AFFILIATION
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%%%
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{\small\itshape
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Department of Physics, Graduate School of Science, \\
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Osaka University, Osaka
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560-0043, Japan}\\
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~\\
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~\\
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%%%
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%%% EMAIL
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%%%
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{\small nam@kuno-g.phys.sci.osaka-u.ac.jp}
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%%%
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%%%
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%%%
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\end{center}
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%%%
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%%% BODY OF ABSTRACT
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%%%
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COMET [1] is an experiment that aims to search for a charged lepton flavor violation
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(CLFV) process, the muon-to-electron conversion in the presence of a nucleus,
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\muec. The process is forbidden in the Standard Model (SM), however is
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predicted to occur in various extensions of SM, such as . Current experimental
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upper limit of the branching ratio is $BR(\mu^{-} + Au \rightarrow e^{-} + Au)
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< 7 \times 10^{-13}$, set by the SINDRUM II experiment [2].
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Using the J-PARC proton beam and the pion capture by
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a solenoidal field, COMET will have a single event sensitivity 10,000 times
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better than the current limit. The COMET collaboration has taken a phased
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approach in which the first phase, COMET Phase-I [3], starts in 2013 and
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initial data taking in around 2016. This paper provides some highlights among
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ongoing R\&D activities.
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%Charged lepton flavor violation (CLFV) has attracted much attention from
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%experimentalists and theorists in particle physics. The CLFV rates are
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%predicted to be in the order of of $O(10^{-54})$ in the Standard Model (SM).
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%Therefore, any experimental observations of CLFV would be an unambiguous signal
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%of new physics beyond the SM. COMET [1] is an experiment
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%that aims to search for a CLFV process of muon-to-electron conversion in the
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%presence of a nucleus, \muec.
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%Using the J-PARC proton beam and the pion capture by
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%a solenoidal field, COMET expects to have a sensitivity a factor of 10,000
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%times that of the current limit. The COMET experiment has taken a phased
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%approach [2] in which the COMET Phase-I (first phase) will start its
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%construction in 2013 and initial data taking in around 2016.
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%The COMET Phase-I will be subjected to significant backgrounds from the
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%products of the nuclear muon capture process. However, experimental data on
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%this matter is insufficient. As so, precise measurements of the products,
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%including protons, neutrons and photons, are required for the design and
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%optimization of the experiment. Detailed of these measurements will be
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%presented.
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%%%
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%%% LIST OF REFERENCES
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%%%
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~\\
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~\\
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~[1] Y.~Kuno {\it et al.} (COMET collaboration), ``A Experimental
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Search for Lepton Flavor Violating \muec Conversion at Sensitivity of
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$10^{-16}$ with A Slow-Extracted Bunched Proton Beam'', J-PARC Proposal, 2007
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and J-PARC Conceptual Design Report, 2009.\\
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~[2] W.~Bertl {\it et al.} (SINDRUM-II collaboration), ``A search for $\mu
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- e$ conversion in muonic gold'', The European Physical Journal C 47 (2006)
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337-346.\\
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~[3] Y.~Kuno {\it et al.} (COMET collaboration), ``Letter of
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Intent of Phase-I for the COMET Experiment at J-PARC'', unpublished, March
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2012.
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%%%
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%%% END OF ABSTRACT
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%%%
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\end{document}
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