High efficiency muon registration system based on scintillator strips

TL;DR

This paper explores designing a high-efficiency muon detection system using scintillator strips with WLS fibers and SiPMs, aiming for 99.99% efficiency crucial for experiments like mu2e and COMET.

Contribution

It introduces a simplified light yield distribution method and simulation validation for optimizing scintillator-based muon detectors at ultra-high efficiency levels.

Findings

High light yield is essential for 99.99% efficiency.

Minimizing gaps between scintillation volumes improves detection.

Simulation results align with experimental data.

Abstract

Experiments such as mu2e (FNAL, USA) and COMET (KEK, Japan), seeking the direct muon-to-electron conversion as part of the study of Charged Leptons Flavor Violation processes, should have a extremely high, up-to 99.99\%, efficiency muon detection system with a view to their subsequent suppression as background. In this article, the possibility to achieve such efficiency for a short and long term is discussed for modules based on 7- or 10-mm-thick but same 40-mm-wide plastic scintillation strips with single 1.2 mm WLS fiber glued into the groove along the strip and using MPPC/SiPM for light detection. A Simplified Light Yield Distribution method to estimate the efficiency of the module was proposed and the simulation results obtained with GEANT 4 for a system based on a 4-by-4 array of 7x40x3000 mm strips compared with the experimental data. Found that for the systems required the high level registration efficiency at the 99.99\% and more, it is important to improve the light yield as much as possible and achieve the gap between neighbor scintillation volumes as small as possible.