Search for heavy neutrinos in \(K^+\to\mu^+\nu_H\) decays

• Published in: arXiv.org 2015-02
• Main Authors: Artamonov, A V, Bassalleck, B, Bhuyan, B, Blackmore, E W, Bryman, D A, Chen, S, I-H, Chiang, I -A Christidi, Cooper, P S, Diwan, M V, Frank, J S, Fujiwara, T, J Hu, Ives, J, Izmaylov, A O, Jaffe, D E, Kabe, S, Kettell, S H, Khabibullin, M M, Khotjantsev, A N, Kitching, P, Kobayashi, M, Komatsubara, T K, Konaka, A, Kudenko, Yu G, Landsberg, L G, Lewis, B, Li, K K, Littenberg, L S, Macdonald, J A, Mildenberger, J, Mineev, O V, Miyajima, M, Mizouchi, K, Muramatsu, N, Nakano, T, Nomachi, M, Nomura, T, Numao, T, Obraztsov, V F, Omata, K, Patalakha, D I, Poutissou, R, Redlinger, G, Sato, T, Sekiguchi, T, Shaikhiev, A T, Shinkawa, T, Strand, R C, Sugimoto, S, Tamagawa, Y, Tschirhart, R, Tsunemi, T, Vavilov, D V, Viren, B, Wang, Zhe, Hanyu Wei, Yershov, N V, Yoshimura, Y, Yoshioka, T
• Format: Article
• Language: English
• Subjects: Background radiation; Decay; Kaons; Neutrinos
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1411.3963

Evidence of a heavy neutrino, \(\nu_H\), in the \(K^+\to\mu^+\nu_H\) decays was sought using the E949 experimental data with an exposure of \(1.70\times 10^{12}\) stopped kaons. With the major background from the radiative \(K^+\to\mu^+\nu_\mu\gamma\) decay understood and suppressed, upper limits (90% C.L.) on the neutrino mixing matrix element between muon and heavy neutrino, \(|U_{\mu H}|^2\), were set at the level of \(10^{-7}\) to \(10^{-9}\) for the heavy neutrino mass region 175 to 300 MeV/\(c^2\).