ArticleAbudinén F, Adachi I, Aggarwal L, Aihara H, Akopov N, Aloisio A, Anh Ky N, Asner DM, Atmacan H,
... Show More Aushev T, Aushev V, Babu V, Bahinipati S, Bambade P, Banerjee S, Bansal S, Baudot J, Baur A, Beaubien A, Becker J, Behera PK, Bennett JV, Bernieri E, Bernlochner FU, Bertemes M, Bertholet E, Bessner M, Bhuyan B, Bianchi F, Bilka T, Biswas D, Bobrov A, Bodrov D, Bolz A, Bozek A, Bračko M, Branchini P, Browder TE, Budano A, Bussino S, Campajola M, Casarosa G, Cecchi C, Chekelian V, Chen C, Chen YQ, Cheon BG, Chilikin K, Chirapatpimol K, Cho HE, Cho K, Cho SJ, Choi SK, Choudhury S, Cinabro D, Corona L, Cunliffe S, Dattola F, de Marino G, De Nardo G, De Nuccio M, De Pietro G, de Sangro R, Destefanis M, Dey S, De Yta-Hernandez A, Dhamija R, Di Canto A, Di Capua F, Dingfelder J, Doležal Z, Domínguez Jiménez I, Dong TV, Dorigo M, Dort K, Dossett D, Dreyer S, Dubey S, Dujany G, Eliachevitch M, Epifanov D, Feichtinger P, Ferber T, Ferlewicz D, Fillinger T, Finck C, Finocchiaro G, Flood K, Fodor A, Forti F, Frey A, Fulsom BG, Ganiev E, Garcia-Hernandez M, Gaur V, Gaz A, Gellrich A, Giordano R, Giri A, Gobbo B, Godang R, Goldenzweig P, Gradl W, Granderath S, Graziani E, Greenwald D, Gu T, Gudkova K, Guilliams J, Hadjivasiliou C, Hara K, Hara T, Hayasaka K, Hayashii H, Hazra S, Hearty C, Hedges MT, Heredia de la Cruz I, Hernández Villanueva M, Hershenhorn A, Higuchi T, Hill EC, Hoek M, Hohmann M, Hsu CL, Iijima T, Inami K, Inguglia G, Ipsita N, Ishikawa A, Ito S, Itoh R, Iwasaki M, Jackson P, Jacobs WW, Jaffe DE, Jang EJ, Ji QP, Jia S, Jin Y, Junkerkalefeld H, Kakuno H, Kaliyar AB, Kandra J, Kang KH, Karl R, Karyan G, Kawasaki T, Ketter C, Kichimi H, Kiesling C, Kim CH, Kim DY, Kim KH, Kim YK, Kinoshita K, Kodyš P, Koga T, Kohani S, Kojima K, Konno T, Korobov A, Korpar S, Kovalenko E, Kowalewski R, Kraetzschmar TMG, Križan P, Krokovny P, Kuhr T, Kumar R, Kumara K, Kunigo T, Kwon YJ, Lacaprara S, Lai YT, Lam T, Lange JS, Laurenza M, Leboucher R, Lee SC, Li LK, Li YB, Libby J, Lieret K, Liu QY, Liventsev D, Longo S, Lozar A, Lueck T, Lyu C, Maggiora M, Maiti R, Maity S, Manfredi R, Manoni E, Marcello S, Marinas C, Martel L, Martini A, Massaccesi L, Masuda M, Matsuoka K, McKenna JA, Meier F, Merola M, Metzner F, Milesi M, Miller C, Miyabayashi K, Mohanty GB, Molina-Gonzalez N, Moneta S, Moon H, Mrvar M, Nakamura I, Nakamura KR, Nakao M, Nakayama H, Narimani Charan A, Naruki M, Natkaniec Z, Natochii A, Nayak L, Nayak M, Nisar NK, Nishida S, Nishimura K, Ogawa S, Ono H, Oskin P, Pakhlova G, Paladino A, Panta A, Pardi S, Parham K, Park H, Park SH, Passeri A, Patra S, Paul S, Pedlar TK, Piccolo M, Piilonen LE, Pinna Angioni G, Podesta-Lerma PLM, Podobnik T, Pokharel S, Polat L, Praz C, Prell S, Prencipe E, Prim MT, Purwar H, Rad N, Rados P, Raiz S, Ramirez Morales A, Reif M, Reiter S, Remnev M, Ripp-Baudot I, Rizzo G, Robertson SH, Rodríguez Pérez D, Roney JM, Rostomyan A, Rout N, Sahoo D, Sanders DA, Sandilya S, Santelj L, Sato Y, Scavino B, Schueler J, Schwanda C, Seino Y, Selce A, Senyo K, Serrano J, Sevior ME, Sfienti C, Shillington T, Shiu JG, Sibidanov A, Simon F, Singh JB, Skorupa J, Soffer A, Sokolov A, Solovieva E, Spataro S, Spruck B, Starič M, Stefkova S, Stottler ZS, Stroili R, Sumihama M, Sumisawa K, Sutcliffe W, Suzuki SY, Svidras H, Tabata M, Takizawa M, Tamponi U, Tanaka S, Tanida K, Tanigawa H, Tenchini F, Tiwary R, Tonelli D, Torassa E, Toutounji N, Trabelsi K, Uchida M, Ueda I, Uematsu Y, Uglov T, Unger K, Unno Y, Uno K, Uno S, Ushiroda Y, Vahsen SE, van Tonder R, Varner GS, Varvell KE, Vinokurova A, Vitale L, Vobbilisetti V, Waheed E, Wakeling HM, Wang E, Wang MZ, Warburton A, Watanabe M, Watanuki S, Welsch M, Wessel C, Windel H, Won E, Xu XP, Yabsley BD, Yamada S, Yan W, Yang SB, Ye H, Yin JH, Yoshihara K, Yuan CZ, Yusa Y, Zani L, Zhang Y, Zhilich V, Zhou QD, Zhou XY, Zhukova VI, Žlebčík R, Belle II Collaboration.Phys Rev Lett. 2023 Feb 17;130(7):071804.
The dark photon A^{'} and the dark Higgs boson h^{'} are hypothetical particles predicted in many dark sector models. We search for the simultaneous production of A^{'} and h^{'} in the dark Higgsstrahlung process e^{+}e^{-}→A^{'}h^{'} with A^{'}→μ^{+}μ^{-} and h^{'} invisible in electron-positron collisions at a center-of-mass energy of 10.58 GeV in data collected by the Belle II experiment in 2019. With an integrated luminosity of 8.34 fb^{-1}, we observe no evidence for signal. We obtain exclusion limits at 90% Bayesian credibility in the range of 1.7-5.0 fb on the cross section and in the range of 1.7×10^{-8}-200×10^{-8} on the effective coupling ϵ^{2}×α_{D} for the A^{'} mass in the range of 4.0 GeV/c^{2}<M_{A^{'}}<9.7 GeV/c^{2} and for the h^{'} mass M_{h^{'}}<M_{A^{'}}, where ϵ is the mixing strength between the standard model and the dark photon and α_{D} is the coupling of the dark photon to the dark Higgs boson. Our limits are the first in this mass range.