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arXiv · 2209.09547

Measurement of decay-time dependent $CP$ violation in $B^0 \rightarrow K^0_S K^0_S K^0_S$ using 2019--2021 Belle II data

Belle II Collaboration·F. Abudinén·I. Adachi·K. Adamczyk·L. Aggarwal·P. Ahlburg·H. Ahmed·J. K. Ahn·H. Aihara·N. Akopov·A. Aloisio·F. Ameli·L. Andricek·N. Anh Ky·D. M. Asner·H. Atmacan·V. Aulchenko·T. Aushev·V. Aushev·T. Aziz·V. Babu·S. Bacher·H. Bae·S. Baehr·S. Bahinipati·A. M. Bakich·P. Bambade·Sw. Banerjee·S. Bansal·M. Barrett·G. Batignani·J. Baudot·M. Bauer·A. Baur·A. Beaubien·A. Beaulieu·J. Becker·P. K. Behera·J. V. Bennett·E. Bernieri·F. U. Bernlochner·V. Bertacchi·M. Bertemes·E. Bertholet·M. Bessner·S. Bettarini·V. Bhardwaj·B. Bhuyan·F. Bianchi·T. Bilka·S. Bilokin·D. Biswas·A. Bobrov·D. Bodrov·A. Bolz·A. Bondar·G. Bonvicini·A. Bozek·M. Bračko·P. Branchini·N. Braun·R. A. Briere·T. E. Browder·D. N. Brown·A. Budano·L. Burmistrov·S. Bussino·M. Campajola·L. Cao·G. Casarosa·C. Cecchi·D. Červenkov·M. -C. Chang·P. Chang·R. Cheaib·P. Cheema·V. Chekelian·C. Chen·Y. Q. Chen·Y. -T. Chen·B. G. Cheon·K. Chilikin·K. Chirapatpimol·H. -E. Cho·K. Cho·S. -J. Cho·S. -K. Choi·S. Choudhury·D. Cinabro·L. Corona·L. M. Cremaldi·S. Cunliffe·T. Czank·S. Das·N. Dash·F. Dattola·E. De La Cruz-Burelo·S. A. De La Motte·G. de Marino·G. De Nardo
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Abstract

We report a measurement of decay-time dependent $CP$-violating parameters in $B^0 \rightarrow K^0_S K^0_S K^0_S$ decays. We use $(198.0 \pm 3.0) \times 10^6\ B\overline{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle II detector at the SuperKEKB asymmetric-energy $e^+e^-$ collider. The observed mixing-induced and direct $CP$ violation parameters are $\mathcal{S} = -1.86\ _{-0.46}^{+0.91}~{\rm (stat)} \pm 0.09~{\rm (syst)}$ and $\mathcal{A} = -0.22\ _{-0.27}^{+0.30}~{\rm (stat)} \pm 0.04~{\rm (syst)}$, respectively.

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Belle II Collaboration, F. Abudinén, I. Adachi, K. Adamczyk, L. Aggarwal, P. Ahlburg, H. Ahmed, J. K. Ahn, H. Aihara, N. Akopov, A. Aloisio, F. Ameli, L. Andricek, N. Anh Ky, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, V. Aushev, T. Aziz, V. Babu, S. Bacher, H. Bae, S. Baehr, S. Bahinipati, A. M. Bakich, P. Bambade, Sw. Banerjee, S. Bansal, M. Barrett, G. Batignani, J. Baudot, M. Bauer, A. Baur, A. Beaubien, A. Beaulieu, J. Becker, P. K. Behera, J. V. Bennett, E. Bernieri, F. U. Bernlochner, V. Bertacchi, M. Bertemes, E. Bertholet, M. Bessner, S. Bettarini, V. Bhardwaj, B. Bhuyan, F. Bianchi, T. Bilka, S. Bilokin, D. Biswas, A. Bobrov, D. Bodrov, A. Bolz, A. Bondar, G. Bonvicini, A. Bozek, M. Bračko, P. Branchini, N. Braun, R. A. Briere, T. E. Browder, D. N. Brown, A. Budano, L. Burmistrov, S. Bussino, M. Campajola, L. Cao, G. Casarosa, C. Cecchi, D. Červenkov, M. -C. Chang, P. Chang, R. Cheaib, P. Cheema, V. Chekelian, C. Chen, Y. Q. Chen, Y. -T. Chen, B. G. Cheon, K. Chilikin, K. Chirapatpimol, H. -E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, S. Choudhury, D. Cinabro, L. Corona, L. M. Cremaldi, S. Cunliffe, T. Czank, S. Das, N. Dash, F. Dattola, E. De La Cruz-Burelo, S. A. De La Motte, G. de Marino, G. De Nardo. 2022-09-20. Measurement of decay-time dependent $CP$ violation in $B^0 \rightarrow K^0_S K^0_S K^0_S$ using 2019--2021 Belle II data. https://arxiv.org/abs/2209.09547

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