Characterizing the energy resolution of MeV-scale signals in the MicroBooNE LArTPC using monoenergetic features of ²⁰⁸Tl radioactive decay

A proper understanding of the capabilities and fidelity of low-energy reconstruction is crucial for taking advantage of MeV-scale neutrino physics opportunities in LArTPCs. This talk will present an analysis resulting in the first-ever demonstration of LArTPC energy resolution in the MeV regime. A measurement of the resolution of energy reconstruction in the MicroBooNE LArTPC at ~1.5 MeV was performed using monoenergetic signals generated by ²⁰⁸Tl decay gamma-rays pair-producing in the detector. This study provides a pathway for MeV-scale monoenergetic energy calibrations in future LArTPC experiments.