Reconstruction of cascade-type neutrino events in KM3NeT/ARCA

Abstract

KM3NeT is a future research infrastructure hosting the next-generation underwater neutrino observatory in the Mediterranean Sea. Within KM3NeT, the ARCA detector will be devoted to the observation of high-energy cosmic neutrinos both in diffuse and point source mode. The discovery of cosmic high energy neutrinos by the IceCube collaboration with a large fraction of shower-like events has led to the recognition of the particular importance of this channel at high(est) energies. While the neutrinos detected by IceCube are compatible with a diffuse distribution, good angular resolution is crucial for the identification of possible sources. Using Monte Carlo simulations, dedicated cascade reconstruction algorithms have been developed for KM3NeT/ARCA allowing for an efficient discrimination of showers from the main background of high energy atmospheric muon bundles and a high precision in the determination of the kinematic variables of the cascades. The optical properties of water and the new technology of KM3NeT with the multi-PMT digital optical module make it possible to reach an energy resolution of less than 10% and a median angular resolution of less than 2 degrees for high energy cascades taking place within the instrumented volume. The reconstruction methods and the results obtained are presented.