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arXiv · 2209.05154

Measurement of the branching fractions and $CP$ asymmetries of $B^+ \rightarrow \pi^+ \pi^0$ and $B^+ \rightarrow K^+ \pi^0$ decays in 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·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·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·M. De Nuccio·G. De Pietro
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Abstract

We determine the branching fractions ${\mathcal{B}}$ and $CP$ asymmetries ${\mathcal{A}_{{\it CP}}}$ of the decays $B^+ \rightarrow \pi^+ \pi^0$ and $B^+ \rightarrow K^+ \pi^0$. The results are based on a data set containing 198 million bottom-antibottom meson pairs corresponding to an integrated luminosity of $190\;\text{fb}^{-1}$ recorded by the Belle II detector in energy-asymmetric electron-positron collisions at the $\Upsilon (4S)$ resonance. We measure ${\mathcal{B}(B^+ \rightarrow \pi^+ \pi^0) = (6.12 \pm 0.53 \pm 0.53)\times 10^{-6}}$, ${\mathcal{B}(B^+ \rightarrow K^+ \pi^0) = (14.30 \pm 0.69 \pm 0.79)\times 10^{-6}}$, ${\mathcal{A}_{{\it CP}}(B^+ \rightarrow \pi^+ \pi^0) = -0.085 \pm 0.085 \pm 0.019}$, and ${\mathcal{A}_{{\it CP}}(B^+ \rightarrow K^+ \pi^0) = 0.014 \pm 0.047 \pm 0.010}$, where the first uncertainties are statistical and the second are systematic. These results improve a previous Belle II measurement and agree with the world averages.

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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, 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, 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, M. De Nuccio, G. De Pietro. 2022-09-12. Measurement of the branching fractions and $CP$ asymmetries of $B^+ \rightarrow \pi^+ \pi^0$ and $B^+ \rightarrow K^+ \pi^0$ decays in 2019-2021 Belle II data. https://arxiv.org/abs/2209.05154

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