Search for Nucleon Decay into Charged Anti-lepton plus Meson in Super-Kamiokande I and II


Abstract in English

Searches for a nucleon decay into a charged anti-lepton (e^+ or {mu}^+) plus a light meson ({pi}^0, {pi}^-, {eta}, {rho}^0, {rho}^-, {omega}) were performed using the Super-Kamiokande I and II data. Twelve nucleon decay modes were searched for. The total exposure is 140.9 kiloton cdot years, which includes a 91.7 kiloton cdot year exposure (1489.2 live days) of Super-Kamiokande-I and a 49.2 kiloton cdot year exposure (798.6 live days) of Super-Kamiokande-II. The number of candidate events in the data was consistent with the atmospheric neutrino background expectation. No significant evidence for a nucleon decay was observed in the data. Thus, lower limits on the nucleon partial lifetime at 90% confidence level were obtained. The limits range from 3.6 times 10^31 to 8.2 times 10^33 years, depending on the decay modes.

Download