@article{oai:oist.repo.nii.ac.jp:00001869,
 author = {Adachi, I. and Ahlburg, P. and Aihara, H. and Akopov, N. and Aloisio, A. and Anh Ky, N. and Asner, D. M. and Atmacan, H. and Aushev, T. and Aushev, V. and Aziz, T. and Babu, V. and Baehr, S. and Bambade, P. and Banerjee, Sw. and Bansal, V. and Barrett, M. and Baudot, J. and Becker, J. and Behera, P. K. and Bennett, J. V. and Bernieri, E. and Bernlochner, F. U. and Bertemes, M. and Bessner, M. and Bettarini, S. and Bianchi, F. and Biswas, D. and Bozek, A. and Bračko, M. and Branchini, P. and Briere, R. A. and Browder, T. E. and Budano, A. and Burmistrov, L. and Bussino, S. and Campajola, M. and Cao, L. and Casarosa, G. and Cecchi, C. and Červenkov, D. and Chang, M.-C. and Cheaib, R. and Chekelian, V. and Chen, Y. Q. and Chen, Y.-T. and Cheon, B. G. and Chilikin, K. and Cho, K. and Cho, S. and Choi, S.-K. and Choudhury, S. and Cinabro, D. and Corona, L. and Cremaldi, L. M. and Cunliffe, S. and Czank, T. and Dattola, F. and De La Cruz-Burelo, E. and De Nardo, G. and De Nuccio, M. and De Pietro, G. and de Sangro, R. and Destefanis, M. and Dey, S. and De Yta-Hernandez, A. and Di Capua, F. and Doležal, Z. and Domínguez Jiménez, I. and Dong, T. V. and Dort, K. and Dossett, D. and Dubey, S. and Duell, S. and Dujany, G. and Eidelman, S. and Eliachevitch, M. and Fast, J. E. and Ferber, T. and Ferlewicz, D. and Finocchiaro, G. and Fiore, S. and Fodor, A. and Forti, F. and Fulsom, B. G. and Ganiev, E. and Garcia-Hernandez, M. and Garg, R. and Gaur, V. and Gaz, A. and Gellrich, A. and Gemmler, J. and Geßler, T. and Giordano, R. and Giri, A. and Gobbo, B. and Godang, R. and Goldenzweig, P. and Golob, B. and Gomis, P. and Gradl, W. and Graziani, E. and Greenwald, D. and Guan, Y. and Hadjivasiliou, C. and Halder, S. and Hara, T. and Hartbrich, O. and Hayasaka, K. and Hayashii, H. and Hearty, C. and Hedges, M. T. and Heredia de la Cruz, I. and Hernández Villanueva, M. and Hershenhorn, A. and Higuchi, T. and Hill, E. C. and Hoek, M. and Hsu, C.-L. and Hu, Y. and Iijima, T. and Inami, K. and Inguglia, G. and Irakkathil Jabbar, J. and Ishikawa, A. and Itoh, R. and Iwasaki, Y. and Jacobs, W. W. and Jaffe, D. E. and Jang, E.-J. and Jeon, H. B. and Jia, S. and Jin, Y. and Joo, C. and Joo, K. K. and Kahn, J. and Kakuno, H. and Kaliyar, A. B. and Kandra, J. and Karyan, G. and Kato, Y. and Kawasaki, T. and Kim, B. H. and Kim, C.-H. and Kim, D. Y. and Kim, K.-H. and Kim, S.-H. and Kim, Y. K. and Kim, Y. and Kimmel, T. D. and Kindo, H. and Kleinwort, C. and Kodyš, P. and Koga, T. and Kohani, S. and Komarov, I. and Korpar, S. and Kovalchuk, N. and Kraetzschmar, T. M. G. and Križan, P. and Kroeger, R. and Krokovny, P. and Kuhr, T. and Kumar, J. and Kumar, M. and Kumar, R. and Kumara, K. and Kurz, S. and Kuzmin, A. and Kwon, Y.-J. and Lacaprara, S. and La Licata, C. and Lanceri, L. and Lange, J. S. and Lautenbach, K. and Lee, I.-S. and Lee, S. C. and Leitl, P. and Levit, D. and Li, L. K. and Li, Y. B. and Libby, J. and Lieret, K. and Li Gioi, L. and Liptak, Z. and Liu, Q. Y. and Liventsev, D. and Longo, S. and Luo, T. and Maeda, Y. and Maggiora, M. and Manoni, E. and Marcello, S. and Marinas, C. and Martini, A. and Masuda, M. and Matsuda, T. and Matsuoka, K. and Matvienko, D. and Meggendorfer, F. and Mei, J. C. and Meier, F. and Merola, M. and Metzner, F. and Milesi, M. and Miller, C. and Miyabayashi, K. and Miyake, H. and Mizuk, R. and Azmi, K. and Mohanty, G. B. and Moon, T. and Morii, T. and Moser, H.-G. and Mueller, F. and Müller, F. J. and Muller, Th. and Muroyama, G. and Mussa, R. and Nakano, E. and Nakao, M. and Nayak, M. and Nazaryan, G. and Neverov, D. and Niebuhr, C. and Nisar, N. K. and Nishida, S. and Nishimura, K. and Nishimura, M. and Oberhof, B. and Ogawa, K. and Onishchuk, Y. and Ono, H. and Onuki, Y. and Oskin, P. and Ozaki, H. and Pakhlov, P. and Pakhlova, G. and Paladino, A. and Panta, A. and Paoloni, E. and Park, H. and Paschen, B. and Passeri, A. and Pathak, A. and Paul, S. and Pedlar, T. K. and Peruzzi, I. and Peschke, R. and Pestotnik, R. and Piccolo, M. and Piilonen, L. E. and Popov, V. and Praz, C. and Prencipe, E. and Prim, M. T. and Purohit, M. V. and Rados, P. and Rasheed, R. and Reiter, S. and Remnev, M. and Resmi, P. K. and Ripp-Baudot, I. and Ritter, M. and Rizzo, G. and Rizzuto, L. B. and Robertson, S. H. and Rodríguez Pérez, D. and Roney, J. M. and Rosenfeld, C. and Rostomyan, A. and Rout, N. and Russo, G. and Sahoo, D. and Sakai, Y. and Sandilya, S. and Sangal, A. and Santelj, L. and Sartori, P. and Sato, Y. and Savinov, V. and Scavino, B. and Schueler, J. and Schwanda, C. and Seddon, R. M. and Seino, Y. and Selce, A. and Senyo, K. and Sfienti, C. and Shen, C. P. and Shiu, J.-G. and Shwartz, B. and Sibidanov, A. and Simon, F. and Sobie, R. J. and Soffer, A. and Sokolov, A. and Solovieva, E. and Spataro, S. and Spruck, B. and Starič, M. and Stefkova, S. and Stottler, Z. S. and Stroili, R. and Strube, J. and Sumihama, M. and Sumiyoshi, T. and Summers, D. J. and Suzuki, S. Y. and Tabata, M. and Takizawa, M. and Tamponi, U. and Tanaka, S. and Tanida, K. and Taniguchi, N. and Taras, P. and Tenchini, F. and Torassa, E. and Trabelsi, K. and Tsuboyama, T. and Uchida, M. and Unger, K. and Unno, Y. and Uno, S. and Ushiroda, Y. and Vahsen, S. E. and van Tonder, R. and Varner, G. S. and Varvell, K. E. and Vinokurova, A. and Vitale, L. and Vossen, A. and Wakai, M. and Wakeling, H. M. and Wan Abdullah, W. and Wang, C. H. and Wang, M.-Z. and Warburton, A. and Watanabe, M. and Webb, J. and Wehle, S. and Wessel, C. and Wiechczynski, J. and Windel, H. and Won, E. and Yabsley, B. and Yamada, S. and Yan, W. and Yang, S. B. and Ye, H. and Yin, J. H. and Yonenaga, M. and Yuan, C. Z. and Yusa, Y. and Zani, L. and Zhang, Z. and Zhilich, V. and Zhou, Q. D. and Zhou, X. Y. and Zhukova, V. I.},
 issue = {14},
 journal = {Physical Review Letters},
 month = {Apr},
 note = {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 Lμ − Lτ theory, into upper limits on the Z′ coupling constant at the level of 5 × 10⁻² − 1 for Mz′ ≤ 6 GeV/c².},
 title = {Search for an Invisibly Decaying Z′ Boson at Belle II in e⁺e⁻→μ⁺μ⁻(e±μ∓) Plus Missing Energy Final States},
 volume = {124},
 year = {2020}
}