A Novel Cosmic Ray Tagger System for Liquid Argon TPC Neutrino Detectors

The Fermilab Short Baseline Neutrino (SBN) program aims to observe and reconstruct thousands of neutrino-argon interactions with its three detectors (SBND, MicroBooNE, and ICARUS-T600), using their hundred-ton scale Liquid Argon Time Projection Chambers to perform a rich physics analysis program, in particular focused on the search for sterile neutrinos. Given the relatively shallow depth of the detectors, the continuous flux of cosmic ray particles crossing their volumes introduces a constant background which can be falsely identified as part of the event of interest. Here we present the Cosmic Ray Tagger (CRT) system, a novel technique to tag and identify these crossing particles using scintillation modules which measure their time and coordinates relative to the internal events to the neutrino detector, with the intent of mitigating their effect in the event tracking reconstruction