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arXiv · 2404.08133

Search for Rare $b \to d\ell^+\ell^-$ Transitions at Belle

Belle·Belle II Collaborations·:·I. Adachi·L. Aggarwal·H. Aihara·N. Akopov·A. Aloisio·S. Al Said·D. M. Asner·H. Atmacan·V. Aushev·M. Aversano·R. Ayad·V. Babu·H. Bae·S. Bahinipati·P. Bambade·Sw. Banerjee·S. Bansal·M. Barrett·J. Baudot·A. Beaubien·F. Becherer·J. Becker·K. Belous·J. V. Bennett·F. U. Bernlochner·V. Bertacchi·M. Bertemes·E. Bertholet·M. Bessner·S. Bettarini·F. Bianchi·L. Bierwirth·T. Bilka·D. Biswas·A. Bobrov·D. Bodrov·A. Bolz·J. Borah·A. Bozek·M. Bračko·P. Branchini·R. A. Briere·T. E. Browder·A. Budano·S. Bussino·M. Campajola·L. Cao·G. Casarosa·C. Cecchi·J. Cerasoli·M. -C. Chang·P. 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·Y. Choi·S. Choudhury·J. Cochran·L. Corona·S. Das·F. Dattola·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·R. Dhamija·F. Di Capua·J. Dingfelder·Z. Doležal·T. V. Dong·M. Dorigo·K. Dort·D. Dossett·S. Dreyer·S. Dubey·K. Dugic·G. Dujany·P. Ecker·D. Epifanov·P. Feichtinger·T. Ferber·D. Ferlewicz·T. Fillinger·C. Finck·G. Finocchiaro·A. Fodor
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Abstract

We present the results of a search for the $b \to d\ell^+\ell^-$ flavor-changing neutral-current rare decays $B^{+, 0} \to (\eta, \omega, \pi^{+,0}, \rho^{+, 0}) e^+e^-$ and $B^{+, 0} \to (\eta, \omega, \pi^{0}, \rho^{+}) \mu^+\mu^-$ using a $711$ fb$^{-1}$ data sample that contains $772 \times 10^{6}$ $B\overline{B}$ events. The data were collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We find no evidence for signal and set upper limits on branching fractions at the $90\%$ confidence level in the range $(3.8 - 47) \times 10^{-8}$ depending on the decay channel. The obtained limits are the world's best results. This is the first search for the channels $B^{+, 0} \to (\omega, \rho^{+,0}) e^+e^-$ and $B^{+, 0} \to (\omega, \rho^{+})\mu^+\mu^-$.

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Belle, Belle II Collaborations, :, I. Adachi, L. Aggarwal, H. Aihara, N. Akopov, A. Aloisio, S. Al Said, D. M. Asner, H. Atmacan, V. Aushev, M. Aversano, R. Ayad, V. Babu, H. Bae, S. Bahinipati, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, J. Baudot, A. Beaubien, F. Becherer, J. Becker, K. Belous, J. V. Bennett, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, F. Bianchi, L. Bierwirth, T. Bilka, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, J. Borah, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, J. Cerasoli, M. -C. Chang, P. 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, Y. Choi, S. Choudhury, J. Cochran, L. Corona, S. Das, F. Dattola, 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, R. Dhamija, F. Di Capua, J. Dingfelder, Z. Doležal, T. V. Dong, M. Dorigo, K. Dort, D. Dossett, S. Dreyer, S. Dubey, K. Dugic, G. Dujany, P. Ecker, D. Epifanov, P. Feichtinger, T. Ferber, D. Ferlewicz, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor. 2024-04-11. Search for Rare $b \to d\ell^+\ell^-$ Transitions at Belle. https://doi.org/10.1103/physrevlett.133.101804

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