233 lines
11 KiB
TeX
233 lines
11 KiB
TeX
%--the poster is one beamer frame, so we have to start with:
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\begin{frame}[t]
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%--to seperate the poster in columns we can use the columns environment
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\begin{columns}[t] % the [t] options aligns the columns content at the top
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\begin{column}{0.28\paperwidth}% the right size for a 3-column layout
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%--abstract block--------------------------------------------------------
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\begin{alertblock}{Introduction}
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Charged lepton flavor violation (CLFV) has attracted much attention
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from experimentalists and theorists in particle physics. The CLFV rates
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are predicted to be in the order of of O($10^{-54}$) in the Standard
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Model.
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Therefore, any observation of CLFV processes would be an
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unambiguous signal for physics beyond the Standard Model. The COMET is
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an experiment that aims to search for a CLFV process of
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muon-to-electron conversion in the presence of a nucleus, \muec. Using
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the J-PARC proton beam and the pion capture by a solenoidal
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field, COMET expects to have a sensitivity a factor of 10,000 times
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that of the current limit. The COMET experiment has taken a phased
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approach 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. Some more
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details of COMET Phase-I and its related issues will be presented.
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\end{alertblock}
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\begin{alertblock}{Staging approach of the COMET}
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The proposed J-PARC mid-term plan includes the construction of the
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COMET beamline. This will provide the proton beamline for COMET and
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part of the muon beamline in the south area of the J-PARC Hadron
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Experimental Hall. We consider a staged approach for COMET: “COMET
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Phase-I” and “COMET Phase-II”.
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For the COMET Phase-I, we will construct the first 90 degrees of the
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muon beamline so that a muon beam can be extracted to the experimental
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area. Then, we will:
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1) make a direct measurement of the proton beam extinction and other
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potential back- ground sources for the COMET Phase-II ex- periment,
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using the actual COMET beamline, and
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2) carry out a search for e conversion with a singe-event
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sensitivity (S.E.S.) of 3 1015, which is better than achieved
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by SINDRUM-II.
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After these measurements, the muon transport will be extended up
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to 180 degrees for the COMET Phase-II. We will start the e
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conversion search with S.E.S. of 3 1017 sensitivity with an
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electron spectrometer and detectors
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\begin{figure}[h!]
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\begin{center}
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\includegraphics[width=0.95\onecolwid]{figs/cometfull}
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\end{center}
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\caption{Schematic lay out of the COMET Phase I and COMET
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Phase II}
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\label{fig:cometscheme}
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\end{figure}
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\begin{figure}[h!]
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\begin{center}
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\includegraphics[width=0.95\onecolwid]{figs/cometphase1}
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\end{center}
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\caption{Schematic lay out of the COMET Phase I and COMET
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Phase II}
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\label{fig:cometp1}
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\end{figure}
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\end{alertblock}
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\end{column}
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%===rightcolumn=================================================================
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% here the the middle and right column are put into one big column, this allows
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% to change between 2 and 3 column style
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\begin{column}{0.60\paperwidth} %thats the big right column
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\begin{block}{The new measurement of charged particles emission
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from muon capture}
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\begin{itemize}
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\item A joint collaboration between COMET and Mu2e
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\item Goals of the experiment:
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\begin{itemize}
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\item[$\bullet$] measure \textcolor{red}{rate and energy
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spectra} of the charged
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particles (p, d, $\alpha$) emitted after muon capture on
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some targets:
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\begin{itemize}
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\item [-] Al: default target of COMET and Mu2e
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\item [-] Ti: possible target for future $\mu-e$
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conversion experiments
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\item [-] Si: active target, for cross-checking against
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previous experiment, and studying the energy loss of
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charged particles inside the targets
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\end{itemize}
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\item[$\bullet$] required precision: \textcolor{red}{5\%}
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for both the rate and the
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energy spectra in the range from 2.5 $-$ 12 MeV
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\end{itemize}
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\item Will be conducted at TRIUMF (Canada) and PSI
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(Switzerland).
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\end{itemize}
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\end{block}
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\vskip1ex
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% Methods
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\begin{block}{Methods}
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\begin{figure}[]
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\includegraphics[width=0.95\twocolwid]{figs/setupa}
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\caption{Experimental setup: schematic view (left) and image (right)}
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\label{fig:setup}
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\end{figure}
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\begin{minipage}[t]{\onecolwid}
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\begin{itemize}
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\item Low momentum muon beam: to ensure a high rate of stopped
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muons, and a well determined range of muons in the targets. A
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cloud muon of 30 $-$ 34 MeV/c from a surface muon channel is
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optimal.
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\item The charged particles are measured by dE/dx method
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by two pairs of silicon detectors. Active area of each silicon
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detector is 5$\times$5 cm$^2$, the dE detectors are 65 $\mu m$
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thick, and the E detectors are 1500 $\mu m$ thick.
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\end{itemize}
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\end{minipage} % Do not put another blank line after this line because
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%that will mess up the alignment of the two minipages
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\begin{minipage}[t]{\onecolwid}
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\begin{itemize}
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\item Muon normalization: muonic X-ray measurement by a germanium
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detector.
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\item Correction for energy loss of charged particles in the
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targets: using a response function obtained from the use of the
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active silicon target, where the energy loss can be measured. A
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waveform digitizer will be used to readout signals from the
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active target.
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\end{itemize}
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\end{minipage}
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\end{block}
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\vskip2ex
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%===two right columns===========================================================
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% we have to give the total width for the column wich is equal to the sum of
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% two colums and the space between them, this is needed to make shure the two
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% cols take all the space of the 'mother' column
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\begin{columns}[t,totalwidth=0.60\paperwidth]
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% and then we put in two normal sized columns
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\begin{column}{0.28\paperwidth}
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%--the Left block-----------------------------------------------------------
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\begin{block}{Calculations}
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\begin{itemize}
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\item Using Geant4, with assumptions:
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\begin{itemize}
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\item [$\bullet$] Muon momentum 30 MeV/c, momentum spread 5\%.
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\item [$\bullet$] Muon intensity: 10$^4$ muons/sec.
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\item [$\bullet$] Proton emission rate is 0.15 per muon capture,
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the same value as that is being used in COMET designing
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calculations
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\item [$\bullet$] Energy resolution (FWHM) of silicon detectors
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are: 140 keV for the 65 $\mu m$-thick detectors, and 40 keV for
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the 140 $\mu m$-thick detectors.
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\item [$\bullet$] Thickness of the beam counter scintillator: 0.5 mm
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\end{itemize}
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\item Simulation results of particle identification and rate
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estimation is shown in Figure \ref{fig:dEdx} and Table
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\ref{tb:rates}.
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\end{itemize}
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\vskip2ex
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\begin{figure}[]
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\includegraphics[width=0.95\onecolwid]{figs/dEdx}
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\caption{Particle identification with two silicon detectors}
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\label{fig:dEdx}
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\end{figure}
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\end{block}
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\end{column}
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%--the Right block--------------------------------------------------------------
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\begin{column}{\onecolwid}
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\begin{alertblock}{Proton beam}
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\end{alertblock}
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\vskip2ex
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\begin{block}{Plan}
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\begin{itemize}
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\item July 2012: submitted the proposal to TRIUMF as experiment
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S1371, requested 36 shifts (3 weeks) beam time
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\item September 2012: the proposal was accepted with high priority
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\item Late November 2012: beam test
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\item Early 2013: physics run, 36 shifts
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\item A proposal will be submitted to PSI
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\end{itemize}
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\end{block}
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\vskip2ex
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\begin{block}{References}
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\small{\begin{thebibliography}{99}
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%\bibitem{cdr} The COMET Collaboration, ``Conceptual Design Report for
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%Experimental Search for Lepton Flavor Violating $\mu^--e^-$
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%Conversion at
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%Sensitivity of $10^{-16}$ with a Slow-Extracted Bunched Proton Beam
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%(COMET)'', KEK-2009-10
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\bibitem{loi} The COMET Collaboration, ``Letter of Intent for Phase-I
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of the COMET Experiment at J-PARC'', J-PARC-2012-3
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\bibitem{sidata} S. E. Sobottka and E. L. Wills, ``Energy Spectrum
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of Charged Particles Emitted Following Muon Capture in Si$^{28}$'',
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Phys. Rev. Lett. \textbf{20} (1968) 596-598.
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\end{thebibliography}}
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\end{block}
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\end{column}
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\end{columns}
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%--wide text without block------------------------------------------------------
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%Those pictures where drawn with the TikZ package, which is a perfect tool if
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%you want to draw pictures or plot functions or data directly in \LaTeX. To
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%get an impression of the possibilities of this package have a look at its
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%manual \cite{pgf}. It is even possible to wonderfull frames around posters.
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%\vskip2ex
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\vskip3ex
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%--Conclusion block-------------------------------------------------------------
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% \begin{alertblock}{Conclusion}
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% As you can see it is possible to make your poster very colorfull. But in
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% most cases this will this will overload your poster. If you don't change
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% the color settings you will get the default look, which consits of some
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% shades of the jacobs blue and some decent green highlights. These colors
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% where chosen carefully to keep a consistent look of the poster. The
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% \emph{cpbgposter} style is installed our office computers, so you should be
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% able to compile this example out of the box with pdflatex. If you want to
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% work on your computer make sure that you have a recent TeX distribution
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% (TeXlive 2008, Miktex) and download the beamerthemecpbgposter.sty file from
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% our teamwork page and put it in your local TeX directory.
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%
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% If you have any questions, critics, ideas or if you just want to praise the
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% awesome dude who created this insanely great poster style then don't
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% hastitate to write an email to \emph{j.liebers@jacobs-university.de}
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%% guess what this command is god for!
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% \makeruleinbox
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%% it works, but causes some underfull/overfull \hbox warnings
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% \begin{center}
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% {\huge\vskip-1ex
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% {\color{nred}H}{\color{norange}a}{\color{nyellow}p}
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% {\color{ngreen}p}{\color{dblue}y}\\
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% \TeX'ing!}
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% \end{center}
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% \end{alertblock}
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\end{column}
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\end{columns}
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\end{frame}
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