학술논문

Search for the baryon number and lepton number violating decays $\tau^-\to \Lambda\pi^-$ and $\tau^-\to \bar{\Lambda}\pi^-$ at Belle II
Document Type
Working Paper
Author
Belle II CollaborationAdachi, I.Aggarwal, L.Ahmed, H.Aihara, H.Akopov, N.Aloisio, A.Althubiti, N.Ky, N. AnhAsner, D. M.Atmacan, H.Aushev, T.Aushev, V.Aversano, M.Ayad, R.Babu, V.Bae, H.Bahinipati, S.Bambade, P.Banerjee, Sw.Bansal, S.Barrett, M.Baudot, J.Baur, A.Beaubien, A.Becherer, F.Becker, J.Bennett, J. V.Bernlochner, F. U.Bertacchi, V.Bertemes, M.Bertholet, E.Bessner, M.Bettarini, S.Bhuyan, B.Bianchi, F.Bierwirth, L.Bilka, T.Biswas, D.Bobrov, A.Bodrov, D.Borah, J.Boschetti, A.Bozek, A.Branchini, P.Browder, T. E.Budano, A.Bussino, S.Campagna, Q.Campajola, M.Casarosa, G.Cecchi, C.Cerasoli, J.Chang, M. -C.Cheaib, R.Cheema, P.Cheon, B. G.Chilikin, K.Chirapatpimol, K.Cho, H. -E.Cho, K.Cho, S. -J.Choi, S. -K.Choudhury, S.Cochran, J.Corona, L.Cui, J. X.De La Cruz-Burelo, E.De La Motte, S. A.De Nardo, G.De Pietro, G.de Sangro, R.Destefanis, M.Dey, S.Dhamija, R.Di Canto, A.Di Capua, F.Dingfelder, J.Doležal, Z.Jiménez, I. DomínguezDong, T. V.Dorigo, M.Dort, K.Dossett, D.Dubey, S.Dujany, G.Ecker, P.Epifanov, D.Eppelt, J.Feichtinger, P.Ferber, T.Fillinger, T.Finck, C.Finocchiaro, G.Fodor, A.Forti, F.Frey, A.Fulsom, B. G.Gabrielli, A.Ganiev, E.Garcia-Hernandez, M.Gaudino, G.Gaur, V.Gaz, A.Gellrich, A.Ghevondyan, G.Ghosh, D.Ghumaryan, H.Giakoustidis, G.Giordano, R.Gironella, P.Glazov, A.Gobbo, B.Godang, R.Goldenzweig, P.Gradl, W.Graziani, E.Greenwald, D.Gruberová, Z.Gudkova, K.Haide, I.Halder, S.Hara, K.Harris, C.Hayashii, H.Hazra, S.Hearty, C.Hedges, M. T.Heidelbach, A.de la Cruz, I. HerediaVillanueva, M. HernándezHiguchi, T.Hoek, M.Hohmann, M.Hoppe, R.Horak, P.Hsu, C. -L.Humair, T.Iijima, T.Inami, K.Ipsita, N.Ishikawa, A.Itoh, R.Iwasaki, M.Jacobs, W. W.Jaffe, D. E.Jang, E. -J.Ji, Q. P.Jia, S.Jin, Y.Junkerkalefeld, H.Kandra, J.Kang, K. H.Karyan, G.Kawasaki, T.Keil, F.Kiesling, C.Kim, D. Y.Kim, J. -Y.Kim, K. -H.Kim, Y. -K.Kinoshita, K.Kodyš, P.Koga, T.Kohani, S.Kojima, K.Korobov, A.Korpar, S.Kovalenko, E.Kowalewski, R.Križan, P.Krokovny, P.Kuhr, T.Kumar, R.Kumara, K.Kuzmin, A.Kwon, Y. -J.Lacaprara, S.Lai, Y. -T.Lalwani, K.Lam, T.Lanceri, L.Lange, J. S.Laurenza, M.Lautenbach, K.Leboucher, R.Lee, M. J.Leo, P.Levit, D.Lewis, P. M.Li, C.Li, L. K.Li, W. Z.Li, Y.Li, Y. B.Libby, J.Lin, J.Liu, M. H.Liu, Q. Y.Liu, Z. Q.Liventsev, D.Longo, S.Lueck, T.Lyu, C.Ma, Y.Maggiora, M.Maharana, S. P.Maiti, R.Maity, S.Mancinelli, G.Manfredi, R.Manoni, E.Mantovano, M.Marcantonio, D.Marcello, S.Marinas, C.Martellini, C.Martens, A.Martini, A.Martinov, T.Massaccesi, L.Masuda, M.Matsuda, T.Matvienko, D.Maurya, S. K.McKenna, J. A.Mehta, R.Meier, F.Merola, M.Miller, C.Mirra, M.Mitra, S.Mondal, S.Moneta, S.Moser, H. -G.Mussa, R.Nakamura, I.Nakao, M.Nakazawa, Y.Naruki, M.Narwal, D.Natkaniec, Z.Natochii, A.Nayak, M.Nazaryan, G.Neu, M.Niebuhr, C.Nishida, S.Ogawa, S.Ono, H.Pakhlov, P.Paoloni, E.Pardi, S.Park, J.Park, K.Park, S. -H.Paschen, B.Passeri, A.Patra, S.Pedlar, T. K.Peschke, R.Pestotnik, R.Piccolo, M.Piilonen, L. E.Podesta-Lerma, P. L. M.Podobnik, T.Pokharel, S.Praz, C.Prell, S.Prencipe, E.Prim, M. T.Purwar, H.Raeuber, G.Raiz, S.Rauls, N.Reif, M.Reiter, S.Remnev, M.Reuter, L.Ripp-Baudot, I.Rizzo, G.Roney, J. M.Rout, N.Sandilya, S.Santelj, L.Savinov, V.Scavino, B.Schnepf, M.Schwanda, C.Seino, Y.Selce, A.Senyo, K.Serrano, J.Sevior, M. E.Sfienti, C.Shan, W.Sharma, C.Shen, C. P.Shi, X. D.Shillington, T.Shimasaki, T.Shiu, J. -G.Shtol, D.Shwartz, B.Sibidanov, A.Simon, F.Singh, J. B.Skorupa, J.Sobie, R. J.Sobotzik, M.Soffer, A.Sokolov, A.Solovieva, E.Song, W.Spataro, S.Spruck, B.Starič, M.Stavroulakis, P.Stefkova, S.Stroili, R.Sue, Y.Sumihama, M.Sumisawa, K.Sutcliffe, W.Suwonjandee, N.Svidras, H.Takahashi, M.Takizawa, M.Tamponi, U.Tanida, K.Tenchini, F.Tittel, O.Tiwary, R.Tonelli, D.Torassa, E.Trabelsi, K.Ueda, I.Unger, K.Unno, Y.Uno, K.Uno, S.Urquijo, P.Vahsen, S. E.van Tonder, R.Varvell, K. E.Veronesi, M.Vismaya, V. S.Vitale, L.Vobbilisetti, V.Volpe, R.Wakai, M.Wallner, S.Wang, E.Wang, M. -Z.Wang, Z.Warburton, A.Watanuki, S.Wessel, C.Won, E.Xu, X. P.Yabsley, B. D.Yamada, S.Yan, W.Yang, S. B.Yelton, J.Yin, J. H.Yoshihara, K.Yuan, C. Z.Zani, L.Zhang, B.Zhou, J. S.Zhou, Q. D.Zhukova, V. I.Žlebčík, R.
Source
Subject
High Energy Physics - Experiment
Language
Abstract
We present a search for the baryon number $B$ and lepton number $L$ violating decays $\tau^- \rightarrow \Lambda \pi^-$ and $\tau^- \rightarrow \bar{\Lambda} \pi^-$ produced from the $e^+e^-\to \tau^+\tau^-$ process, using a 364 fb$^{-1}$ data sample collected by the Belle~II experiment at the SuperKEKB collider. No evidence of signal is found in either decay mode, which have $|\Delta(B-L)|$ equal to $2$ and $0$, respectively. Upper limits at 90\% credibility level on the branching fractions of $\tau^- \rightarrow \Lambda\pi^-$ and $\tau^- \rightarrow \bar{\Lambda}\pi^-$ are determined to be $4.7 \times 10^{-8}$ and $4.3 \times 10^{-8}$, respectively.
Comment: 8 pages, 4 figures