Electron-Muon Ranger: performance in the MICE Muon Beam¶
Abstract¶
The Muon Ionization Cooling Experiment (MICE) will perform a detailed study of ionization cooling to evaluate the feasibility of the technique. To carry out this program, MICE requires an efficient particle-identification (PID) system to identify muons. The Electron-Muon Ranger (EMR) is a fully-active tracking-calorimeter that forms part of the PID system and tags muons that traverse the cooling channel without decaying. The detector is capable of identifying electrons with an efficiency of 98.6%, providing a purity for the MICE beam that exceeds 99.8%. The EMR also proved to be a powerful tool for the reconstruction of muon momenta in the range 100--280 MeV/c.
Paper¶
Published in: 2015 JINST 10 P12012
arXiv: 1510.08306
RAL Preprint: RAL-P-2015-008
DOI: 10.1088/1748-0221/10/12/P12012
Figures¶
Figure 1. Schematic of the MICE Muon Beam line (MMB) and the MICE experiment. (PDF, jpg)
Figure 2. CAD drawing of one EMR plane (top) and cross section of 3 triangular bars (bottom). (PDF, jpg)
Figure 3. The EMR detector installed in the MICE Hall at the end of the preliminary (`Step I') beam line. (PDF, jpg)
Figure 4. Momentum loss fraction of particles travelling from D2 to the EMR, compared to their momentum at D2 (pD2). (PDF, jpg)
Figure 5. Time-of-flight between the TOF1 and TOF2 detectors (TOF1->2) for a `calibration' beam selected with an array of momenta at D2 (pD2). (PDF, jpg)
Figure 6. Continuous Slowing Down Approximation of the mean momentum loss (Dpz) of particles crossing TOF2 with impinging momentum pz. (PDF, jpg)
Figure 7. Continuous Slowing Down Approximation of the mean momentum loss (Dpz) of muons crossing the KL with impinging momentum pz. (PDF, jpg)
Figure 8. EMR event display of the energy deposited by a positron shower (pD2 = 450 MeV/c) in the two projections. (PDF, jpg)
Figure 9. EMR event display of the energy deposited by a mu+ which decays in the detector volume. (PDF, jpg)
Figure 10. Logarithmic scale distributions of the plane density (rhoP) for muons and electrons. The integrated electron sample has been normalised to the number of muons. (PDF, jpg)
Figure 11. Fitted electron shower and muon track in the xz projection. (PDF, jpg)
Figure 12. Logarithmic scale scatter plot of the muon and electron samples in the (chix^2/N, chiy^2/N)$ space. (PDF, jpg)
Figure 13. Percentage of the electron sample tagged as a muon (beta) as a function of the loss (alpha) of real muons for different values on the cut rhoC. The black dot represents the optimal point of the curve. (PDF, jpg)
Figure 14. Percentage of the electron sample tagged as a muon (beta) as a function of the loss of real muons (alpha) for three choices of test statistic xi. The black dot is the optimal point regardless of the choice of test statistic. (PDF, jpg)
Figure 15. Percentage of the electron sample tagged as a muon (beta) versus the loss of real muons (alpha) in the multivariate analysis. The large black triangle is the optimal point. (PDF, jpg)
Figure 16. Percentage of electron contamination and muon loss for different ranges of momentum set at D2 (pD2). (PDF, jpg)
Figure 17. Muon range as a function of the momentum reconstructed from TOF->2. At 280 MeV/c and above, muons can traverse the entire detector without stopping, hence the plateau at R = 816 mm.(PDF, jpg)
Figure 18. Muon range as a function of the initial momentum p0. (PDF, jpg)
Figure 19. Downstream momentum (pd) as a function of the range (R) in the EMR. (PDF, jpg)
Updated by Drielsma, François almost 8 years ago · 28 revisions