1203.4030 (H. Nishino et al.)

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

H. Nishino, K. Abe, Y. Hayato, T. Iida, M. Ikeda, J. Kameda, Y. Koshio, M. Miura, S. Moriyama, M. Nakahata, S. Nakayama, Y. Obayashi, H. Sekiya, M. Shiozawa, Y. Suzuki, A. Takeda, Y. Takenaga, Y. Takeuchi, K. Ueno, K. Ueshima, H. Watanabe, S. Yamada, S. Hazama, I. Higuchi, C. Ishihara, H. Kaji, T. Kajita, K. Kaneyuki, G. Mitsuka, K. Okumura, N. Tanimoto, F. Dufour, E. Kearns, M. Litos, J. L. Raaf, J. L. Stone, L. R. Sulak, M. Goldhaber, K. Bays, J. P. Cravens, W. R. Kropp, S. Mine, C. Regis, M. B. Smy, H. W. Sobel, K. S. Ganezer, J. Hill, W. E. Keig, J. S. Jang, J. Y. Kim, I. T. Lim, J. B. Albert, K. Scholberg, C. W. Walter, R. Wendell, T. Ishizuka, S. Tasaka, J. G. Learned, S. Matsuno, Y. Watanabe, T. Hasegawa, T. Ishida, T. Ishii, T. Kobayashi, T. Nakadaira, K. Nakamura, K. Nishikawa, Y. Oyama, K. Sakashita, T. Sekiguchi, T. Tsukamoto, A. T. Suzuki, A. Minamino, T. Nakaya, M. Yokoyama, Y. Fukuda, Y. Itow, T. Tanaka, C. K. Jung, G. Lopez, C. McGrew, C. Yanagisawa, N. Tamura, Y. Idehara, M. Sakuda, Y. Kuno, M. Yoshida, S. B. Kim, B. S. Yang, H. Okazawa, Y. Choi, H. K. Seo, Y. Furuse, K. Nishijima, Y. Yokosawa, M. Koshiba, Y. Totsuka, M. R. Vagins, S. Chen, Y. Heng, J. Liu, Z. Yang, H. Zhang, D. Kielczewska, K. Connolly, E. Thrane, R. J. Wilkes

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.

View original: http://arxiv.org/abs/1203.4030