diff --git a/EDIT2013poster/contents.tex b/EDIT2013poster/contents.tex index 97ce7f0..2daadbb 100644 --- a/EDIT2013poster/contents.tex +++ b/EDIT2013poster/contents.tex @@ -5,195 +5,126 @@ \begin{column}{0.28\paperwidth}% the right size for a 3-column layout %--abstract block-------------------------------------------------------- \begin{alertblock}{Introduction} - Charged lepton flavor violation (CLFV) has attracted much attention - from experimentalists and theorists in particle physics. The CLFV rates - are predicted to be in the order of of O($10^{-54}$) in the Standard - Model. - - Therefore, any observation of CLFV processes would be an - unambiguous signal for physics beyond the Standard Model. The COMET is - an experiment that aims to search for a CLFV process of - muon-to-electron conversion in the presence of a nucleus, \muec. Using - the J-PARC proton beam and the pion capture by a solenoidal - field, COMET expects to have a sensitivity a factor of 10,000 times - that of the current limit. The COMET experiment has taken a phased - approach in which the COMET Phase-I (first phase) will start its - construction in 2013 and initial data taking in around 2016. Some more - details of COMET Phase-I and its related issues will be presented. + Charged lepton flavor violation (cLFV) has yet to be observed and is + known to be sensitive to new physics beyond the Standard Model (SM). + Various extensions of the SM predicts that cLFV occurs at a detectable + branching ratio. Therefore, from experimental point of view, it is + attractive to search for cLFV with more powerful beams and better + detection technologies. + + Among the cLFV processes, $\mu-e$ conversion, a coherent neutrino-less + conversion of muon to electron in the presence of a nucleus: \muecaz, + is our interest. We have proposed a new search for $\mu -e$ conversion + at J-PARC, the E21 experiment - \textcolor{red}{COMET}( + \textcolor{red}{COherent Muon to Electron Transition}). The single + event sensitivity (SES) of COMET will be $2.6\times10^{-17}$, which is + 10,000 + times better than that of the current experimental limit + set by SINDRUM II at $7\times10^{-13}$. + \end{alertblock} \begin{alertblock}{Staging approach of the COMET} - The proposed J-PARC mid-term plan includes the construction of the - COMET beamline. This will provide the proton beamline for COMET and - part of the muon beamline in the south area of the J-PARC Hadron - Experimental Hall. We consider a staged approach for COMET: “COMET - Phase-I” and “COMET Phase-II”. + In order to realize the COMET experiment, a two-stage approach has been + taken. COMET Phase-I aims at an intermediate SES of $3\times10^{-15}$, + which is an improvement of a factor of 100 compares to SINDRUM II. In + addition, the COMET Phase-I will make direct measurement of the proton + beam extinction and other potential background sources for the COMET + Phase-II experiment, using the actual COMET beamline. - For the COMET Phase-I, we will construct the first 90 degrees of the - muon beamline so that a muon beam can be extracted to the experimental - area. Then, we will: - - 1) make a direct measurement of the proton beam extinction and other - potential back- ground sources for the COMET Phase-II ex- periment, - using the actual COMET beamline, and - - 2) carry out a search for e conversion with a singe-event - sensitivity (S.E.S.) of 3 1015, which is better than achieved - by SINDRUM-II. - After these measurements, the muon transport will be extended up - to 180 degrees for the COMET Phase-II. We will start the e - conversion search with S.E.S. of 3 1017 sensitivity with an - electron spectrometer and detectors \begin{figure}[h!] \begin{center} - \includegraphics[width=0.95\onecolwid]{figs/cometfull} + \includegraphics[width=0.95\onecolwid]{../figs/comet/comet_phase_1} \end{center} - \caption{Schematic lay out of the COMET Phase I and COMET - Phase II} + \caption{Schematic layout of the COMET} \label{fig:cometscheme} \end{figure} + The COMET Phase-I funding has been approved. Experimental hall + construction and beam + line design are in progress, and expected to finish in 2015. The layout + of the COMET beam line at Hadron Hall, J-PARC is shown in the Fig. + \ref{fig:cometbeamline}. For the COMET Phase-I, we will + construct the first 90 degrees of the muon beamline before extracting + to the experimental area. Data taking is expected to start around 2016. + \begin{figure}[h!] \begin{center} - \includegraphics[width=0.95\onecolwid]{figs/cometphase1} + \includegraphics[width=0.95\onecolwid]{../figs/comet/comet_beamline} \end{center} - \caption{Schematic lay out of the COMET Phase I and COMET - Phase II} - \label{fig:cometp1} + \caption{COMET beam line at Hadron hall} + \label{fig:cometbeamline} \end{figure} - \end{alertblock} - \end{column} %===rightcolumn================================================================= % here the the middle and right column are put into one big column, this allows % to change between 2 and 3 column style \begin{column}{0.60\paperwidth} %thats the big right column - \begin{block}{The new measurement of charged particles emission - from muon capture} - \begin{itemize} - \item A joint collaboration between COMET and Mu2e - \item Goals of the experiment: - \begin{itemize} - \item[$\bullet$] measure \textcolor{red}{rate and energy - spectra} of the charged - particles (p, d, $\alpha$) emitted after muon capture on - some targets: - \begin{itemize} - \item [-] Al: default target of COMET and Mu2e - \item [-] Ti: possible target for future $\mu-e$ - conversion experiments - \item [-] Si: active target, for cross-checking against - previous experiment, and studying the energy loss of - charged particles inside the targets - \end{itemize} - \item[$\bullet$] required precision: \textcolor{red}{5\%} - for both the rate and the - energy spectra in the range from 2.5 $-$ 12 MeV - \end{itemize} - \item Will be conducted at TRIUMF (Canada) and PSI - (Switzerland). - \end{itemize} - \end{block} - \vskip1ex - % Methods - \begin{block}{Methods} - \begin{figure}[] - \includegraphics[width=0.95\twocolwid]{figs/setupa} - \caption{Experimental setup: schematic view (left) and image (right)} - \label{fig:setup} - \end{figure} - \begin{minipage}[t]{\onecolwid} - \begin{itemize} - \item Low momentum muon beam: to ensure a high rate of stopped - muons, and a well determined range of muons in the targets. A - cloud muon of 30 $-$ 34 MeV/c from a surface muon channel is - optimal. - \item The charged particles are measured by dE/dx method - by two pairs of silicon detectors. Active area of each silicon - detector is 5$\times$5 cm$^2$, the dE detectors are 65 $\mu m$ - thick, and the E detectors are 1500 $\mu m$ thick. - \end{itemize} - \end{minipage} % Do not put another blank line after this line because - %that will mess up the alignment of the two minipages - \begin{minipage}[t]{\onecolwid} - \begin{itemize} - \item Muon normalization: muonic X-ray measurement by a germanium - detector. - \item Correction for energy loss of charged particles in the - targets: using a response function obtained from the use of the - active silicon target, where the energy loss can be measured. A - waveform digitizer will be used to readout signals from the - active target. - \end{itemize} - \end{minipage} - \end{block} - \vskip2ex + %\begin{block}{} %===two right columns=========================================================== % we have to give the total width for the column wich is equal to the sum of % two colums and the space between them, this is needed to make shure the two % cols take all the space of the 'mother' column - \begin{columns}[t,totalwidth=0.60\paperwidth] - % and then we put in two normal sized columns - \begin{column}{0.28\paperwidth} - %--the Left block----------------------------------------------------------- - \begin{block}{Calculations} - \begin{itemize} - \item Using Geant4, with assumptions: - \begin{itemize} - \item [$\bullet$] Muon momentum 30 MeV/c, momentum spread 5\%. - \item [$\bullet$] Muon intensity: 10$^4$ muons/sec. - \item [$\bullet$] Proton emission rate is 0.15 per muon capture, - the same value as that is being used in COMET designing - calculations - \item [$\bullet$] Energy resolution (FWHM) of silicon detectors - are: 140 keV for the 65 $\mu m$-thick detectors, and 40 keV for - the 140 $\mu m$-thick detectors. - \item [$\bullet$] Thickness of the beam counter scintillator: 0.5 mm - \end{itemize} - \item Simulation results of particle identification and rate - estimation is shown in Figure \ref{fig:dEdx} and Table - \ref{tb:rates}. - \end{itemize} - \vskip2ex - \begin{figure}[] - \includegraphics[width=0.95\onecolwid]{figs/dEdx} - \caption{Particle identification with two silicon detectors} - \label{fig:dEdx} - \end{figure} + %\begin{columns}[t,totalwidth=0.60\paperwidth] + % and then we put in two normal sized columns + \begin{column}{0.28\paperwidth} + \begin{alertblock}{Proton beam} + COMET Phase-I will use an 8 GeV, 1 $\mu$A, slowly extracted proton beam + from the J-PARC main ring (MR). One option for the bunch structure of + the proton beam is shown in Fig \ref{fig:pbeam}. + \begin{figure}[] + \includegraphics[width=0.75\onecolwid]{../figs/comet/comet_pbeam_config} + \caption{COMET proton beam acceleration bunch configuration} + \label{fig:pbeam} + \end{figure} + \end{alertblock} + + %--the Left block----------------------------------------------------------- + \begin{alertblock}{Pion and muon transportation beam} + \begin{figure}[] + \includegraphics[width=0.95\onecolwid]{../figs/comet/comet_p1_det_bg} + \caption{COMET proton beam acceleration bunch configuration} + \label{fig:bg_det} + \end{figure} + \end{alertblock} + %\end{block} + \vskip1ex + % Methods + \vskip2ex + \end{column} + %--the Right block-------------------------------------------------------------- + \begin{column}{\onecolwid} + \begin{alertblock}{Detectors for COMET Phase I} + \end{alertblock} + \vskip2ex + \begin{alertblock}{} + \begin{figure}[] + \includegraphics[width=0.95\onecolwid]{../figs/comet/comet_p1_det_bg} + \caption{COMET proton beam acceleration bunch configuration} + \label{fig:phys_det} + \end{figure} + \end{alertblock} + \vskip2ex + \begin{block}{References} + \small{\begin{thebibliography}{99} + %\bibitem{cdr} The COMET Collaboration, ``Conceptual Design Report for + %Experimental Search for Lepton Flavor Violating $\mu^--e^-$ + %Conversion at + %Sensitivity of $10^{-16}$ with a Slow-Extracted Bunched Proton Beam + %(COMET)'', KEK-2009-10 + \bibitem{loi} The COMET Collaboration, ``Letter of Intent for Phase-I + of the COMET Experiment at J-PARC'', J-PARC-2012-3 + \end{thebibliography}} \end{block} \end{column} - %--the Right block-------------------------------------------------------------- - \begin{column}{\onecolwid} - \begin{alertblock}{Proton beam} - \end{alertblock} - \vskip2ex - \begin{block}{Plan} - \begin{itemize} - \item July 2012: submitted the proposal to TRIUMF as experiment - S1371, requested 36 shifts (3 weeks) beam time - \item September 2012: the proposal was accepted with high priority - \item Late November 2012: beam test - \item Early 2013: physics run, 36 shifts - \item A proposal will be submitted to PSI - \end{itemize} - \end{block} - \vskip2ex - \begin{block}{References} - \small{\begin{thebibliography}{99} - %\bibitem{cdr} The COMET Collaboration, ``Conceptual Design Report for - %Experimental Search for Lepton Flavor Violating $\mu^--e^-$ - %Conversion at - %Sensitivity of $10^{-16}$ with a Slow-Extracted Bunched Proton Beam - %(COMET)'', KEK-2009-10 - \bibitem{loi} The COMET Collaboration, ``Letter of Intent for Phase-I - of the COMET Experiment at J-PARC'', J-PARC-2012-3 - \bibitem{sidata} S. E. Sobottka and E. L. Wills, ``Energy Spectrum - of Charged Particles Emitted Following Muon Capture in Si$^{28}$'', - Phys. Rev. Lett. \textbf{20} (1968) 596-598. - \end{thebibliography}} - \end{block} - \end{column} - \end{columns} + \begin{figure}[h!] + \begin{center} + \includegraphics[width=0.95\twocolwid]{../figs/comet/comet_phase1_tracker.pdf} + \end{center} + \caption{Schematic lay out of the COMET Phase I} + \label{fig:phase1} + \end{figure} + %\end{columns} %--wide text without block------------------------------------------------------ %Those pictures where drawn with the TikZ package, which is a perfect tool if %you want to draw pictures or plot functions or data directly in \LaTeX. To diff --git a/EDIT2013poster/poster.tex b/EDIT2013poster/poster.tex index 8d8f79b..681df23 100755 --- a/EDIT2013poster/poster.tex +++ b/EDIT2013poster/poster.tex @@ -77,6 +77,7 @@ \newcommand{\muenn}{$\mu \rightarrow e \nu \overline{\nu}$~} \newcommand{\muenng}{$\mu \rightarrow e \nu \overline{\nu} \gamma$~} \newcommand{\muec}{$\mu^{-} N \rightarrow e^{-} N$~} +\newcommand{\muecaz}{$\mu^{-} + N(A,Z) \rightarrow e^{-} + N(A,Z)$~} \begin{document} \include{contents} diff --git a/figs/comet/comet_phase_1.png b/figs/comet/comet_phase_1.png index 28bbbb2..909b04c 100644 Binary files a/figs/comet/comet_phase_1.png and b/figs/comet/comet_phase_1.png differ