Adachi I 1 , Ahlburg P 2 , Aihara H 3 , Akopov N 4 , Aloisio A 5 , Anh Ky N 6 Show all authors , Asner DM 7 , Atmacan H 8 , Aushev T 9 , Aushev V 10 , Aziz T 11 , Babu V 12 , Baehr S 13 , Bambade P 14 , Banerjee S 15 , Bansal V 16 , Barrett M 17 , Baudot J 18 , Becker J 13 , Behera PK 19 , Bennett JV 20 , Bernieri E 21 , Bernlochner FU 2 , Bertemes M 22 , Bessner M 23 , Bettarini S 24 , Bianchi F 25 , Biswas D 15 , Bozek A 26 , Bračko M 27 , Branchini P 21 , Briere RA 28 , Browder TE 23 , Budano A 21 , Burmistrov L 14 , Bussino S 21 , Campajola M 5 , Cao L 2 , Casarosa G 24 , Cecchi C 29 , Červenkov D 30 , Chang MC 31 , Cheaib R 32 , Chekelian V 33 , Chen YQ 34 , Chen YT 35 , Cheon BG 36 , Chilikin K 37 , Cho K 38 , Cho S 39 , Choi SK 40 , Choudhury S 41 , Cinabro D 42 , Corona L 24 , Cremaldi LM 20 , Cunliffe S 12 , Czank T 43 , Dattola F 12 , De La Cruz-Burelo E 44 , De Nardo G 5 , De Nuccio M 12 , De Pietro G 21 , de Sangro R 45 , Destefanis M 25 , Dey S 46 , De Yta-Hernandez A 44 , Di Capua F 5 , Doležal Z 30 , Domínguez Jiménez I 47 , Dong TV 48 , Dort K 49 , Dossett D 50 , Dubey S 23 , Duell S 2 , Dujany G 18 , Eidelman S 51 , Eliachevitch M 2 , Fast JE 16 , Ferber T 12 , Ferlewicz D 50 , Finocchiaro G 45 , Fiore S 52 , Fodor A 53 , Forti F 24 , Fulsom BG 16 , Ganiev E 54 , Garcia-Hernandez M 44 , Garg R 55 , Gaur V 56 , Gaz A 57 , Gellrich A 12 , Gemmler J 13 , Geßler T 49 , Giordano R 5 , Giri A 41 , Gobbo B 54 , Godang R 58 , Goldenzweig P 13 , Golob B 27 , Gomis P 59 , Gradl W 60 , Graziani E 21 , Greenwald D 61 , Guan Y 8 , Hadjivasiliou C 16 , Halder S 11 , Hara T 1 , Hartbrich O 23 , Hayasaka K 62 , Hayashii H 63 , Hearty C 64 , Hedges MT 23 , Heredia de la Cruz I 44 , Hernández Villanueva M 20 , Hershenhorn A 32 , Higuchi T 43 , Hill EC 32 , Hoek M 60 , Hsu CL 65 , Hu Y 66 , Iijima T 57 , Inami K 57 , Inguglia G 22 , Irakkathil Jabbar J 13 , Ishikawa A 1 , Itoh R 1 , Iwasaki Y 17 , Jacobs WW 67 , Jaffe DE 7 , Jang EJ 40 , Jeon HB 68 , Jia S 69 , Jin Y 54 , Joo C 43 , Joo KK 70 , Kahn J 13 , Kakuno H 71 , Kaliyar AB 11 , Kandra J 30 , Karyan G 4 , Kato Y 57 , Kawasaki T 72 , Kim BH 73 , Kim CH 36 , Kim DY 74 , Kim KH 39 , Kim SH 36 , Kim YK 39 , Kim Y 75 , Kimmel TD 56 , Kindo H 1 , Kleinwort C 12 , Kodyš P 30 , Koga T 17 , Kohani S 23 , Komarov I 12 , Korpar S 27 , Kovalchuk N 12 , Kraetzschmar TMG 33 , Križan P 27 , Kroeger R 20 , Krokovny P 51 , Kuhr T 76 , Kumar J 28 , Kumar M 77 , Kumar R 78 , Kumara K 42 , Kurz S 12 , Kuzmin A 51 , Kwon YJ 39 , Lacaprara S 79 , La Licata C 43 , Lanceri L 54 , Lange JS 49 , Lautenbach K 49 , Lee IS 36 , Lee SC 68 , Leitl P 33 , Levit D 61 , Li LK 8 , Li YB 80 , Libby J 19 , Lieret K 76 , Li Gioi L 33 , Liptak Z 23 , Liu QY 48 , Liventsev D 17 , Longo S 81 , Luo T 48 , Maeda Y 57 , Maggiora M 25 , Manoni E 29 , Marcello S 25 , Marinas C 59 , Martini A 21 , Masuda M 82 , Matsuda T 83 , Matsuoka K 57 , Matvienko D 51 , Meggendorfer F 33 , Mei JC 48 , Meier F 84 , Merola M 5 , Metzner F 13 , Milesi M 50 , Miller C 81 , Miyabayashi K 63 , Miyake H 1 , Mizuk R 37 , Azmi K 85 , Mohanty GB 11 , Moon T 73 , Morii T 43 , Moser HG 33 , Mueller F 33 , Müller FJ 12 , Muller T 13 , Muroyama G 57 , Mussa R 25 , Nakano E 86 , Nakao M 1 , Nayak M 46 , Nazaryan G 4 , Neverov D 57 , Niebuhr C 12 , Nisar NK 87 , Nishida S 1 , Nishimura K 23 , Nishimura M 17 , Oberhof B 45 , Ogawa K 62 , Onishchuk Y 10 , Ono H 62 , Onuki Y 3 , Oskin P 37 , Ozaki H 1 , Pakhlov P 37 , Pakhlova G 37 , Paladino A 24 , Panta A 20 , Paoloni E 24 , Park H 68 , Paschen B 2 , Passeri A 21 , Pathak A 15 , Paul S 61 , Pedlar TK 88 , Peruzzi I 45 , Peschke R 23 , Pestotnik R 27 , Piccolo M 45 , Piilonen LE 56 , Popov V 37 , Praz C 12 , Prencipe E 89 , Prim MT 13 , Purohit MV 90 , Rados P 12 , Rasheed R 18 , Reiter S 49 , Remnev M 51 , Resmi PK 19 , Ripp-Baudot I 18 , Ritter M 76 , Rizzo G 24 , Rizzuto LB 27 , Robertson SH 64 , Rodríguez Pérez D 47 , Roney JM 64 , Rosenfeld C 91 , Rostomyan A 12 , Rout N 19 , Russo G 5 , Sahoo D 11 , Sakai Y 1 , Sandilya S 8 , Sangal A 8 , Santelj L 27 , Sartori P 79 , Sato Y 92 , Savinov V 87 , Scavino B 60 , Schueler J 23 , Schwanda C 22 , Seddon RM 53 , Seino Y 62 , Selce A 29 , Senyo K 93 , Sfienti C 60 , Shen CP 69 , Shiu JG 35 , Shwartz B 51 , Sibidanov A 81 , Simon F 33 , Sobie RJ 81 , Soffer A 46 , Sokolov A 94 , Solovieva E 37 , Spataro S 25 , Spruck B 60 , Starič M 27 , Stefkova S 12 , Stottler ZS 56 , Stroili R 79 , Strube J 16 , Sumihama M 95 , Sumiyoshi T 71 , Summers DJ 20 , Suzuki SY 1 , Tabata M 96 , Takizawa M 97 , Tamponi U 25 , Tanaka S 1 , Tanida K 98 , Taniguchi N 17 , Taras P 99 , Tenchini F 12 , Torassa E 79 , Trabelsi K 14 , Tsuboyama T 1 , Uchida M 100 , Unger K 13 , Unno Y 36 , Uno S 1 , Ushiroda Y 1 , Vahsen SE 23 , van Tonder R 2 , Varner GS 23 , Varvell KE 65 , Vinokurova A 51 , Vitale L 54 , Vossen A 84 , Wakai M 32 , Wakeling HM 53 , Wan Abdullah W 85 , Wang CH 101 , Wang MZ 35 , Warburton A 53 , Watanabe M 62 , Webb J 50 , Wehle S 12 , Wessel C 2 , Wiechczynski J 24 , Windel H 33 , Won E 75 , Yabsley B 65 , Yamada S 17 , Yan W 34 , Yang SB 75 , Ye H 12 , Yin JH 66 , Yonenaga M 71 , Yuan CZ 66 , Yusa Y 62 , Zani L 24 , Zhang Z 34 , Zhilich V 51 , Zhou QD 17 , Zhou XY 69 , Zhukova VI 37 , Belle II Collaboration

Affiliations 

  • 1 The Graduate University for Advanced Studies (SOKENDAI), Hayama 240-0193
  • 2 University of Bonn, 53115 Bonn
  • 3 Department of Physics, University of Tokyo, Tokyo 113-0033
  • 4 Alikhanyan National Science Laboratory, Yerevan 0036
  • 5 INFN Sezione di Napoli, I-80126 Napoli
  • 6 Institute of Theoretical and Applied Research (ITAR), Duy Tan University, Hanoi 100000, Vietnam
  • 7 Brookhaven National Laboratory, Upton, New York 11973
  • 8 University of Cincinnati, Cincinnati, Ohio 45221
  • 9 Moscow Institute of Physics and Technology, Moscow Region 141700
  • 10 Taras Shevchenko National Univ. of Kiev, Kiev
  • 11 Tata Institute of Fundamental Research, Mumbai 400005
  • 12 Deutsches Elektronen-Synchrotron, 22607 Hamburg
  • 13 Institut für Experimentelle Teilchenphysik, Karlsruher Institut für Technologie, 76131 Karlsruhe
  • 14 Laboratoire de l'Accélérateur Linéaire, IN2P3/CNRS et Université Paris-Sud 11, Centre Scientifique d'Orsay, F-91898 Orsay Cedex
  • 15 University of Louisville, Louisville, Kentucky 40292
  • 16 Pacific Northwest National Laboratory, Richland, Washington 99352
  • 17 High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801
  • 18 Université de Strasbourg, CNRS, IPHC, UMR 7178, 67037 Strasbourg
  • 19 Indian Institute of Technology Madras, Chennai 600036
  • 20 University of Mississippi, University, Mississippi 38677
  • 21 INFN Sezione di Roma Tre, I-00146 Roma
  • 22 Institute of High Energy Physics, Vienna 1050, Austria
  • 23 University of Hawaii, Honolulu, Hawaii 96822
  • 24 INFN Sezione di Pisa, I-56127 Pisa
  • 25 INFN Sezione di Torino, I-10125 Torino
  • 26 H. Niewodniczanski Institute of Nuclear Physics, Krakow 31-342
  • 27 J. Stefan Institute, 1000 Ljubljana
  • 28 Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
  • 29 INFN Sezione di Perugia, I-06123 Perugia
  • 30 Faculty of Mathematics and Physics, Charles University, 121 16 Prague
  • 31 Department of Physics, Fu Jen Catholic University, Taipei 24205
  • 32 University of British Columbia, Vancouver, British Columbia, V6T 1Z1
  • 33 Max-Planck-Institut für Physik, 80805 München
  • 34 University of Science and Technology of China, Hefei 230026
  • 35 Department of Physics, National Taiwan University, Taipei 10617
  • 36 Department of Physics and Institute of Natural Sciences, Hanyang University, Seoul 04763
  • 37 P.N. Lebedev Physical Institute of the Russian Academy of Sciences, Moscow 119991
  • 38 Korea Institute of Science and Technology Information, Daejeon 34141
  • 39 Yonsei University, Seoul 03722
  • 40 Gyeongsang National University, Jinju 52828
  • 41 Indian Institute of Technology Hyderabad, Telangana 502285
  • 42 Wayne State University, Detroit, Michigan 48202
  • 43 Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa 277-8583
  • 44 Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Mexico City 07360
  • 45 INFN Laboratori Nazionali di Frascati, I-00044 Frascati
  • 46 Tel Aviv University, School of Physics and Astronomy, Tel Aviv, 69978
  • 47 Universidad Autonoma de Sinaloa, Sinaloa 80000
  • 48 Key Laboratory of Nuclear Physics and Ion-beam Application (MOE) and Institute of Modern Physics, Fudan University, Shanghai 200443
  • 49 Justus-Liebig-Universität Gießen, 35392 Gießen
  • 50 School of Physics, University of Melbourne, Victoria 3010
  • 51 Budker Institute of Nuclear Physics SB RAS, Novosibirsk 630090
  • 52 INFN Sezione di Roma, I-00185 Roma
  • 53 McGill University, Montréal, Québec, H3A 2T8
  • 54 INFN Sezione di Trieste, I-34127 Trieste
  • 55 Panjab University, Chandigarh 160014
  • 56 Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061
  • 57 Graduate School of Science, Nagoya University, Nagoya 464-8602
  • 58 University of South Alabama, Mobile, Alabama 36688
  • 59 Instituto de Fisica Corpuscular, Paterna 46980
  • 60 Johannes Gutenberg-Universität Mainz, Institut für Kernphysik, D-55099 Mainz
  • 61 Department of Physics, Technische Universität München, 85748 Garching
  • 62 Niigata University, Niigata 950-2181
  • 63 Nara Women's University, Nara 630-8506
  • 64 Institute of Particle Physics (Canada), Victoria, British Columbia V8W 2Y2
  • 65 School of Physics, University of Sydney, New South Wales 2006
  • 66 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049
  • 67 Indiana University, Bloomington, Indiana 47408
  • 68 Kyungpook National University, Daegu 41566
  • 69 Beihang University, Beijing 100191
  • 70 Chonnam National University, Gwangju 61186
  • 71 Tokyo Metropolitan University, Tokyo 192-0397
  • 72 Kitasato University, Sagamihara 252-0373
  • 73 Seoul National University, Seoul 08826
  • 74 Soongsil University, Seoul 06978
  • 75 Korea University, Seoul 02841
  • 76 Ludwig Maximilians University, 80539 Munich
  • 77 Malaviya National Institute of Technology Jaipur, Jaipur 302017
  • 78 Punjab Agricultural University, Ludhiana 141004
  • 79 INFN Sezione di Padova, I-35131 Padova
  • 80 Peking University, Beijing 100871
  • 81 University of Victoria, Victoria, British Columbia, V8W 3P6
  • 82 Earthquake Research Institute, University of Tokyo, Tokyo 113-0032
  • 83 University of Miyazaki, Miyazaki 889-2192
  • 84 Duke University, Durham, North Carolina 27708
  • 85 National Centre for Particle Physics, University Malaya, 50603 Kuala Lumpur
  • 86 Osaka City University, Osaka 558-8585
  • 87 University of Pittsburgh, Pittsburgh, Pennsylvania 15260
  • 88 Luther College, Decorah, Iowa 52101
  • 89 Forschungszentrum Jülich, 52425 Jülich
  • 90 Okinawa Institute of Science and Technology, Okinawa 904-0495
  • 91 University of South Carolina, Columbia, South Carolina 29208
  • 92 Department of Physics, Tohoku University, Sendai 980-8578
  • 93 Yamagata University, Yamagata 990-8560
  • 94 Institute for High Energy Physics, Protvino 142281
  • 95 Gifu University, Gifu 501-1193
  • 96 Chiba University, Chiba 263-8522
  • 97 J-PARC Branch, KEK Theory Center, High Energy Accelerator Research Organization (KEK), Tsukuba 305-0801
  • 98 Advanced Science Research Center, Japan Atomic Energy Agency, Naka 319-1195
  • 99 Université de Montréal, Physique des Particules, Montréal, Québec, H3C 3J7
  • 100 Tokyo Institute of Technology, Tokyo 152-8550
  • 101 National United University, Miao Li 36003
Phys. Rev. Lett., 2020 Apr 10;124(14):141801.
PMID: 32338980 DOI: 10.1103/PhysRevLett.124.141801

Abstract

Theories beyond the standard model often predict the existence of an additional neutral boson, the Z^{'}. Using data collected by the Belle II experiment during 2018 at the SuperKEKB collider, we perform the first searches for the invisible decay of a Z^{'} in the process e^{+}e^{-}→μ^{+}μ^{-}Z^{'} and of a lepton-flavor-violating Z^{'} in e^{+}e^{-}→e^{±}μ^{∓}Z^{'}. We do not find any excess of events and set 90% credibility level upper limits on the cross sections of these processes. We translate the former, in the framework of an L_{μ}-L_{τ} theory, into upper limits on the Z^{'} coupling constant at the level of 5×10^{-2}-1 for M_{Z^{'}}≤6  GeV/c^{2}.

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.