학술논문
Neutron-antineutron oscillation search using a 0.37 megaton-years exposure of Super-Kamiokande
Document Type
article
Author
Abe, K; Bronner, C; Hayato, Y; Ikeda, M; Imaizumi, S; Ito, H; Kameda, J; Kataoka, Y; Miura, M; Moriyama, S; Nagao, Y; Nakahata, M; Nakajima, Y; Nakayama, S; Okada, T; Okamoto, K; Orii, A; Pronost, G; Sekiya, H; Shiozawa, M; Sonoda, Y; Suzuki, Y; Takeda, A; Takemoto, Y; Takenaka, A; Tanaka, H; Yano, T; Akutsu, R; Han, S; Kajita, T; Okumura, K; Tashiro, T; Wang, R; Xia, J; Bravo-Berguño, D; Labarga, L; Marti, Ll; Zaldivar, B; Blaszczyk, FDM; Kearns, E; Gustafson, JD; Raaf, JL; Stone, JL; Wan, L; Wester, T; Bian, J; Griskevich, NJ; Kropp, WR; Locke, S; Mine, S; Smy, MB; Sobel, HW; Takhistov, V; Weatherly, P; Hill, J; Kim, JY; Lim, IT; Park, RG; Bodur, B; Scholberg, K; Walter, CW; Coffani, A; Drapier, O; Hedri, S El; Giampaolo, A; Gonin, M; Mueller, Th A; Paganini, P; Quilain, B; Ishizuka, T; Nakamura, T; Jang, JS; Learned, JG; Anthony, LHV; Sztuc, AA; Uchida, Y; Berardi, V; Catanesi, MG; Radicioni, E; Calabria, NF; Machado, LN; De Rosa, G; Collazuol, G; Iacob, F; Lamoureux, M; Ospina, N; Ludovici, L; Nishimura, Y; Cao, S; Friend, M; Hasegawa, T; Ishida, T; Kobayashi, T; Matsubara, T; Nakadaira, T; Jakkapu, M; Nakamura, K; Oyama, Y; Sakashita, K; Sekiguchi, T
Source
Physical Review D. 103(1)
Subject
Language
Abstract
As a baryon number violating process with ΔB=2, neutron-antineutron oscillation (n→n¯) provides a unique test of baryon number conservation. We have performed a search for n→n¯ oscillation with bound neutrons in Super-Kamiokande, with the full dataset from its first four run periods, representing an exposure of 0.37 Mton-years. The search used a multivariate analysis trained on simulated n→n¯ events and atmospheric neutrino backgrounds and resulted in 11 candidate events with an expected background of 9.3 events. In the absence of statistically significant excess, we derived a lower limit on n¯ appearance lifetime in O16 nuclei of 3.6×1032 years and on the neutron-antineutron oscillation time of τn→n¯>4.7×108 s at 90% C.L.