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arXiv · 1203.4030

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

Kamiokande Collaboration·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
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Abstract

Searches for a nucleon decay into a charged anti-lepton (e^+ or μ^+) plus a light meson (π^0, π^-, η, ρ^0, ρ^-, ω) 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.

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Kamiokande Collaboration, 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. 2012-06-22. Search for Nucleon Decay into Charged Anti-lepton plus Meson in Super-Kamiokande I and II. https://doi.org/10.1103/physrevd.85.112001

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