Neutrino interactions at COMET

Abstract: The experimental search for coherent neutrinoless conversion of muon to electron in the presence of a nucleus, aims to probe the possibility of charged lepton flavour violation. The COMET experiment at J-PARC is one such setup offering unprecedented statistical reach, with single event sensitivities down to $\mathcal{O}$ ($\mathrm{10^{-17}}$). Its successor experiment - PRISM, planned as the final stage, is expected to take this bound further down by two orders of magnitude. The electrons from standard model decay of bound muons are considered the most formidable physics background to the detection of these conversion electrons. Keeping in view the high stopped muon statistics for COMET and PRISM, the rate of charged current interaction of decay neutrinos with nuclear protons is also non-negligible. In this work, we perform a calculation of the positron event rates expected due to interactions of electron antineutrinos with Al target protons in the COMET setup. About $\mathrm{7\pm1}$ such $\mathrm{e^{+}}$ events per $\mathrm{10^{18}}$stopped muons are expected.