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arXiv · 1508.05530

Search for Nucleon and Dinucleon Decays with an Invisible Particle and a Charged Lepton in the Final State at the Super-Kamiokande Experiment

Abstract

Search results for nucleon decays $p \rightarrow e^+X$, $p \rightarrow μ^+X$, $n \rightarrow νγ$ (where $X$ is an invisible, massless particle) as well as dinucleon decays $np \rightarrow e^+ν$, $np \rightarrow μ^+ν$ and $np \rightarrow τ^+ν$ in the Super-Kamiokande experiment are presented. Using single-ring data from an exposure of 273.4 kton $\cdot$ years, a search for these decays yields a result consistent with no signal. Accordingly, lower limits on the partial lifetimes of $τ_{p \rightarrow e^+X} > 7.9 \times 10^{32}$ years, $τ_{p \rightarrow μ^+X} > 4.1 \times 10^{32}$ years, $τ_{n \rightarrow νγ} > 5.5 \times 10^{32}$ years, $τ_{np \rightarrow e^+ν} > 2.6 \times 10^{32}$ years, $τ_{np \rightarrow μ^+ν} > 2.2 \times 10^{32}$ years and $τ_{np \rightarrow τ^+ν} > 2.9 \times 10^{31}$ years at a $90 \% $ confidence level are obtained. Some of these searches are novel.

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BibTeXRIS

V. Takhistov, K. Abe, Y. Haga, Y. Hayato, M. Ikeda, K. Iyogi, J. Kameda, Y. Kishimoto, M. Miura, S. Moriyama, M. Nakahata, T. Nakajima, Y. Nakano, S. Nakayama, A. Orii, H. Sekiya, M. Shiozawa, A. Takeda, H. Tanaka, T. Tomura, R. A. Wendell, T. Irvine, T. Kajita, I. Kametani, K. Kaneyuki, Y. Nishimura, E. Richard, K. Okumura, L. Labarga, P. Fernandez, J. Gustafson, C. Kachulis, E. Kearns, J. L. Raaf, J. L. Stone, L. R. Sulak, S. Berkman, C. M. Nantais, H. A. Tanaka, S. Tobayama, M. Goldhaber, G. Carminati, W. R. Kropp, S. Mine, P. Weatherly, A. Renshaw, M. B. Smy, H. W. Sobel, K. S. Ganezer, B. L. Hartfiel, J. Hill, N. Hong, J. Y. Kim, I. T. Lim, A. Himmel, Z. Li, K. Scholberg, C. W. Walter, T. Wongjirad, T. Ishizuka, S. Tasaka, J. S. Jang, J. G. Learned, S. Matsuno, S. N. Smith, M. Friend, T. Hasegawa, T. Ishida, T. Ishii, T. Kobayashi, T. Nakadaira, K. Nakamura, Y. Oyama, K. Sakashita, T. Sekiguchi, T. Tsukamoto, A. T. Suzuki, Y. Takeuchi, T. Yano, S. Hirota, K. Huang, K. Ieki, T. Kikawa, A. Minamino, T. Nakaya, K. Suzuki, S. Takahashi, Y. Fukuda, K. Choi, Y. Itow, T. Suzuki, P. Mijakowski, K. Frankiewicz, J. Hignight, J. Imber, C. K. Jung, X. Li, J. L. Palomino, M. J. Wilking, C. Yanagisawa. 2015-09-21. Search for Nucleon and Dinucleon Decays with an Invisible Particle and a Charged Lepton in the Final State at the Super-Kamiokande Experiment. https://doi.org/10.1103/physrevlett.115.121803

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