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arXiv · 2412.12338

Observation of the decay $B^0 \to J/\psi \omega$ at Belle II

Belle II Collaboration·I. Adachi·L. Aggarwal·H. Ahmed·H. Aihara·N. Akopov·M. Alhakami·A. Aloisio·N. Althubiti·N. Anh Ky·D. M. Asner·H. Atmacan·V. Aushev·M. Aversano·R. Ayad·V. Babu·N. K. Baghel·S. Bahinipati·P. Bambade·Sw. Banerjee·M. Barrett·J. Baudot·A. Baur·A. Beaubien·J. Becker·J. V. Bennett·V. Bertacchi·M. Bertemes·E. Bertholet·M. Bessner·S. Bettarini·B. Bhuyan·F. Bianchi·D. Biswas·A. Bobrov·D. Bodrov·A. Bolz·A. Bondar·J. Borah·A. Boschetti·A. Bozek·M. Bračko·P. Branchini·N. Brenny·R. A. Briere·T. E. Browder·A. Budano·S. Bussino·Q. Campagna·M. Campajola·G. Casarosa·C. Cecchi·J. Cerasoli·M. -C. Chang·R. Cheaib·P. Cheema·C. Chen·B. G. Cheon·K. Chilikin·K. Chirapatpimol·H. -E. Cho·K. Cho·S. -J. Cho·S. -K. Choi·S. Choudhury·J. Cochran·L. Corona·J. X. Cui·E. De La Cruz-Burelo·S. A. De La Motte·G. de Marino·G. De Nardo·G. De Pietro·R. de Sangro·M. Destefanis·S. Dey·A. Di Canto·F. Di Capua·J. Dingfelder·Z. Doležal·I. Domínguez Jiménez·T. V. Dong·X. Dong·M. Dorigo·D. Dossett·K. Dugic·G. Dujany·P. Ecker·D. Epifanov·J. Eppelt·P. Feichtinger·T. Ferber·T. Fillinger·C. Finck·G. Finocchiaro·A. Fodor·F. Forti·B. G. Fulsom·A. Gabrielli·E. Ganiev
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Abstract

We measure the branching fraction of the decay $B^0 \to J/\psi \omega$ using data collected with the Belle II detector at the SuperKEKB collider. The data contain $(387 \pm 6) \times 10^6$ $B\overline{B}$ meson pairs produced in energy-asymmetric $e^+e^-$ collisions at the $\Upsilon (4S)$ resonance. The measured branching fraction $\mathcal{B}(B^0 \to J/\psi \omega) = \left( 2.16 \pm 0.30 \pm 0.14 \right) \times 10^{-5}$, where the first uncertainty is statistical and the second is systematic, is more precise than previous results and constitutes the first observation of the decay with a significance of $6.5$ standard deviations.

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Belle II Collaboration, I. Adachi, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, M. Alhakami, A. Aloisio, N. Althubiti, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aushev, M. Aversano, R. Ayad, V. Babu, N. K. Baghel, S. Bahinipati, P. Bambade, Sw. Banerjee, M. Barrett, J. Baudot, A. Baur, A. Beaubien, J. Becker, J. V. Bennett, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, F. Bianchi, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, J. Borah, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, N. Brenny, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, G. Casarosa, C. Cecchi, J. Cerasoli, M. -C. Chang, R. Cheaib, P. Cheema, C. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H. -E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, S. Choudhury, J. Cochran, L. Corona, J. X. Cui, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo, G. De Pietro, R. de Sangro, M. Destefanis, S. Dey, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, I. Domínguez Jiménez, T. V. Dong, X. Dong, M. Dorigo, D. Dossett, K. Dugic, G. Dujany, P. Ecker, D. Epifanov, J. Eppelt, P. Feichtinger, T. Ferber, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, B. G. Fulsom, A. Gabrielli, E. Ganiev. 2024-12-16. Observation of the decay $B^0 \to J/\psi \omega$ at Belle II. https://doi.org/10.1103/physrevd.111.032012

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