HEP-Astro Seminar | First Measurement of Missing Energy Due to Nuclear Effects in Monoenergetic Neutrino Charged Current Interactions

The JSNS2 experiment is able to measure mono-energetic (235.5 MeV) kaon decay-at-rest neutrino interactions with unprecedented clarity; using a dataset from our first year of running, we observe 621 interactions with an estimated signal-to-background rate of 3.3:1. And – because every neutrino has a known energy – our measurement of outgoing particles' total energy spectrum provides direct information about the nuclear effects involved. Observing these nuclear effects, in turn, provides significant constraints on models of quasi-elastic neutrino-nucleus scattering, a crucial ingredient for many modern day neutrino experiments. Here I’ll present the details of our measurement and provide an outlook for future improvements.