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arXiv · 1901.03230

Atmospheric Neutrino Oscillation Analysis With Improved Event Reconstruction in Super-Kamiokande IV

Kamiokande Collaboration·M. Jiang·K. Abe·C. Bronner·Y. Hayato·M. Ikeda·K. Iyogi·J. Kameda·Y. Kato·Y. Kishimoto·Ll. Marti·M. Miura·S. Moriyama·T. Mochizuki·M. Nakahata·Y. Nakajima·Y. Nakano·S. Nakayama·T. Okada·K. Okamoto·A. Orii·G. Pronost·H. Sekiya·M. Shiozawa·Y. Sonoda·A. Takeda·A. Takenaka·H. Tanaka·T. Yano·R. Akutsu·T. Kajita·Y. Nishimura·K. Okumura·R. Wang·J. Xia·L. Labarga·P. Fernandez·F. d. M. Blaszczyk·C. Kachulis·E. Kearns·J. L. Raaf·J. L. Stone·S. Sussman·S. Berkman·J. Bian·N. J. Griskevich·W. R. Kropp·S. Locke·S. Mine·P. Weatherly·M. B. Smy·H. W. Sobel·V. Takhistov·K. S. Ganezer·J. Hill·J. Y. Kim·I. T. Lim·R. G. Park·B. Bodur·K. Scholberg·C. W. Walter·O. Drapier·M. Gonin·J. Imber·Th. A. Mueller·P. Paganini·T. Ishizuka·T. Nakamura·J. S. Jang·K. Choi·J. G. Learned·S. Matsuno·R. P. Litchfield·A. A. Sztuc·Y. Uchida·M. O. Wascko·N. F. Calabria·M. G. Catanesi·R. A. Intonti·E. Radicioni·G. De Rosa·A. Ali·G. Collazuol·F. Iacob·L. Ludovici·S. Cao·M. Friend·T. Hasegawa·T. Ishida·T. Kobayashi·T. Nakadaira·K. Nakamura·Y. Oyama·K. Sakashita·T. Sekiguchi·T. Tsukamoto·KE. Abe·M. Hasegawa·Y. Isobe·H. Miyabe
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Abstract

A new event reconstruction algorithm based on a maximum likelihood method has been developed for Super-Kamiokande. Its improved kinematic and particle identification capabilities enable the analysis of atmospheric neutrino data in a detector volume 32% larger than previous analyses and increases sensitivity to the neutrino mass hierarchy. Analysis of a 253.9 kton-year exposure of the Super-Kamiokande IV atmospheric neutrino data has yielded a weak preference for the normal hierarchy, disfavoring the inverted hierarchy at 74% assuming oscillations at the best fit of the analysis.

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Kamiokande Collaboration, M. Jiang, K. Abe, C. Bronner, Y. Hayato, M. Ikeda, K. Iyogi, J. Kameda, Y. Kato, Y. Kishimoto, Ll. Marti, M. Miura, S. Moriyama, T. Mochizuki, M. Nakahata, Y. Nakajima, Y. Nakano, S. Nakayama, T. Okada, K. Okamoto, A. Orii, G. Pronost, H. Sekiya, M. Shiozawa, Y. Sonoda, A. Takeda, A. Takenaka, H. Tanaka, T. Yano, R. Akutsu, T. Kajita, Y. Nishimura, K. Okumura, R. Wang, J. Xia, L. Labarga, P. Fernandez, F. d. M. Blaszczyk, C. Kachulis, E. Kearns, J. L. Raaf, J. L. Stone, S. Sussman, S. Berkman, J. Bian, N. J. Griskevich, W. R. Kropp, S. Locke, S. Mine, P. Weatherly, M. B. Smy, H. W. Sobel, V. Takhistov, K. S. Ganezer, J. Hill, J. Y. Kim, I. T. Lim, R. G. Park, B. Bodur, K. Scholberg, C. W. Walter, O. Drapier, M. Gonin, J. Imber, Th. A. Mueller, P. Paganini, T. Ishizuka, T. Nakamura, J. S. Jang, K. Choi, J. G. Learned, S. Matsuno, R. P. Litchfield, A. A. Sztuc, Y. Uchida, M. O. Wascko, N. F. Calabria, M. G. Catanesi, R. A. Intonti, E. Radicioni, G. De Rosa, A. Ali, G. Collazuol, F. Iacob, L. Ludovici, S. Cao, M. Friend, T. Hasegawa, T. Ishida, T. Kobayashi, T. Nakadaira, K. Nakamura, Y. Oyama, K. Sakashita, T. Sekiguchi, T. Tsukamoto, KE. Abe, M. Hasegawa, Y. Isobe, H. Miyabe. 2019-01-10. Atmospheric Neutrino Oscillation Analysis With Improved Event Reconstruction in Super-Kamiokande IV. https://doi.org/10.1093/ptep/ptz015

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