Study on the accidental background of the JSNS $$^2$$ experiment
D. Lee (High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki, Japan); S. Ajimura (Research Center for Nuclear Physics, Osaka University, Osaka, Japan); M. Cheoun (Department of Physics, Soongsil University, Seoul, 06978, Korea); J. Choi (Laboratory for High Energy Physics, Dongshin University, Chonnam, 58245, Korea); J. Choi (Department of Fire Safety, Seoyeong University, Gwangju, 61268, Korea); et al - Show all 58 authors
JSNS $$^2$$ (J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) is an experiment that searches for sterile neutrinos via the observation of $$\bar{\nu }_{\mu } \rightarrow \bar{\nu }_{e}$$ appearance oscillations using muon decay-at-rest neutrinos. The JSNS $$^2$$ experiment performed data taking from 2021. In this manuscript, a study of the accidental background is presented. The rate of the accidental background is ( $$9.29\pm 0.39) \times 10^{-8}$$ /spill with 0.75 MW beam power and comparable to the expected number of signal events.
