Expected performance of Cosmic Muon Veto Detector

Abstract The India-based Neutrino Observatory (INO) collaboration has established a miniICAL detector, at the transit campus of IICHEP, Madurai, India, which serves as a prototype detector of the larger Iron-Calorimeter detector (ICAL). The purpose of miniICAL lies in unraveling the intricate physics and engineering challenges inherent in constructing and operating a substantial ICAL-type detector. To explore the feasibility of building a large-scale neutrino experiment at shallow depths the collaboration has embarked upon the construction of a Cosmic Muon Veto Detector (CMVD) around the miniICAL detector. The primary objective of this endeavor revolves around attaining a veto efficiency surpassing 99.99%, while simultaneously maintaining a false-positive rate lower than 10 -5 . The CMVD system is based on extruded plastic scintillators (EPS) and utilizes wavelength-shifting fibers to collect scintillation photons and uses silicon photomultipliers (SiPMs) as photo-transducers. A software tool is developed for CMVD and is integrated with the existing miniICAL consisting of RPC detectors. The simulation is tuned to include properties of EPSs and WLS fibers, measured efficiencies, and time resolutions of EPSs. Measured spectra and noise in SiPMs are also taken into account. The muon tracks in the RPCs are used to estimate the muon veto efficiency of CMVD to arrive at efficient muon veto criteria. With improved veto efficiency of cosmic muons, the CMVD experiment will help to pave the way for future large-scale shallow-depth neutrino experiments e.g. INO-type experiments, enhancing our understanding of neutrino properties.