A feasibility study of extruded plastic scintillator embedding WLS fiber for AMoRE-II muon veto [CL]

http://arxiv.org/abs/2201.08034


AMoRE-II is the second phase of the Advanced Molybdenum-based Rare process Experiment aiming to search for the neutrino-less double beta decay of 100Mo isotopes using ~ 200 kg of molybdenum-containing cryogenic detectors. The AMoRE-II needs to keep the background level below 10-5 counts/keV/kg/year with various methods to maximize the sensitivity. One of the methods is to have the experiment be carried out in a deep underground free from the cosmic ray backgrounds. The AMoRE-II will run at Yemilab with ~ 1,000 m depth. Even in such a deep underground environment, however, there are still survived cosmic muons which can affect the measurement and should be excluded as much as possible. A muon veto detector is necessary to reject muon-induced particles coming to the inner detector where the molybdate cryogenic detectors are located. We have studied the possibility of using an extruded plastic scintillator and wavelength shifting fiber together with SiPM as a muon veto system. We obtained a muon flux of 428.4 events/m2/day at Yangyang underground laboratory using a prototype muon detector, in agreement with a COSINE-100 measurement. The estimated event rate in the AMoRE-II muon veto system for a 135 m2 total veto area is 2.04 events/s.

Read this paper on arXiv…

J. Seo, W. Kim, Y. Kim, et. al.
Fri, 21 Jan 22
45/60

Comments: 9 pages, 8 figures, 2 tables