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arXiv · 2411.00306

Measurement of the time-integrated CP asymmetry in $D^{0}\rightarrow K^{0}_{S}K^{0}_{S}$ decays using Belle and Belle II data

Belle·Belle II Collaborations·:·I. Adachi·L. Aggarwal·H. Ahmed·H. Aihara·N. Akopov·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·S. Bansal·M. Barrett·M. Bartl·J. Baudot·A. Beaubien·J. Becker·J. V. Bennett·V. Bertacchi·M. Bertemes·E. Bertholet·M. Bessner·S. Bettarini·B. Bhuyan·D. Biswas·A. Bobrov·D. Bodrov·A. Bolz·A. Boschetti·A. Bozek·M. Bračko·P. Branchini·R. A. Briere·T. E. Browder·A. Budano·S. Bussino·Q. Campagna·M. Campajola·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·S. Choudhury·J. Cochran·L. Corona·J. X. Cui·S. Das·E. De La Cruz-Burelo·S. A. De La Motte·G. De Pietro·R. de Sangro·M. Destefanis·A. Di Canto·F. Di Capua·J. Dingfelder·Z. Doležal·T. V. Dong·M. Dorigo·D. Dossett·G. Dujany·P. Ecker·J. Eppelt·P. Feichtinger·T. Ferber·T. Fillinger·C. Finck·G. Finocchiaro·A. Fodor·F. Forti·B. G. Fulsom·A. Gabrielli·E. Ganiev·G. Gaudino·V. Gaur·A. Gaz·A. Gellrich·G. Ghevondyan·D. Ghosh·H. Ghumaryan
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Abstract

We measure the time-integrated CP asymmetry in $D^{0} \rightarrow K^{0}_{S}K^{0}_{S}$ decays reconstructed in $e^{+}e^{-} \rightarrow c\overline{c}$ events collected by the Belle and Belle II experiments. The corresponding data samples have integrated luminosities of 980 fb$^{-1}$ and 428 fb$^{-1}$, respectively. The $D^{0}$ decays are required to originate from the $D^{*+} \rightarrow D^{0}\pi^{+}$ decay, which determines the charm flavor at production time. A control sample of $D^{0} \rightarrow K^{+}K^{-}$ decays is used to correct for production and detection asymmetries. The result, $(-1.4\pm1.3{\rm(stat)}\pm0.1{\rm (syst)})\%$, is consistent with previous determinations and with CP symmetry.

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Belle, Belle II Collaborations, :, I. Adachi, L. Aggarwal, H. Ahmed, H. Aihara, N. Akopov, 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, S. Bansal, M. Barrett, M. Bartl, J. Baudot, A. Beaubien, J. Becker, J. V. Bennett, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, B. Bhuyan, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Boschetti, A. Bozek, M. Bračko, P. Branchini, R. A. Briere, T. E. Browder, A. Budano, S. Bussino, Q. Campagna, M. Campajola, 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, S. Choudhury, J. Cochran, L. Corona, J. X. Cui, S. Das, E. De La Cruz-Burelo, S. A. De La Motte, G. De Pietro, R. de Sangro, M. Destefanis, A. Di Canto, F. Di Capua, J. Dingfelder, Z. Doležal, T. V. Dong, M. Dorigo, D. Dossett, G. Dujany, P. Ecker, J. Eppelt, P. Feichtinger, T. Ferber, T. Fillinger, C. Finck, G. Finocchiaro, A. Fodor, F. Forti, B. G. Fulsom, A. Gabrielli, E. Ganiev, G. Gaudino, V. Gaur, A. Gaz, A. Gellrich, G. Ghevondyan, D. Ghosh, H. Ghumaryan. 2024-11-01. Measurement of the time-integrated CP asymmetry in $D^{0}\rightarrow K^{0}_{S}K^{0}_{S}$ decays using Belle and Belle II data. https://doi.org/10.1103/physrevd.111.012015

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