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arXiv · 2111.12337

Measurement of the branching fraction and $CP$ asymmetry for $B\to\bar{D}^{0} \pi$ decays

Belle Collaboration·T. Bloomfield·M. E. Sevior·I. Adachi·H. Aihara·S. Al Said·D. M. Asner·V. Aulchenko·T. Aushev·R. Ayad·V. Babu·S. Bahinipati·P. Behera·J. Bennett·M. Bessner·T. Bilka·J. Biswal·A. Bobrov·G. Bonvicini·A. Bozek·M. Bračko·T. E. Browder·M. Campajola·L. Cao·D. Červenkov·M. -C. Chang·V. Chekelian·A. Chen·B. G. Cheon·K. Chilikin·H. E. Cho·K. Cho·S. -J. Cho·S. -K. Choi·Y. Choi·S. Choudhury·D. Cinabro·S. Cunliffe·S. Das·N. Dash·G. De Nardo·R. Dhamija·F. Di Capua·Z. Doležal·T. V. Dong·S. Dubey·S. Eidelman·D. Epifanov·T. Ferber·D. Ferlewicz·B. G. Fulsom·R. Garg·V. Gaur·A. Garmash·A. Giri·P. Goldenzweig·C. Hadjivasiliou·S. Halder·O. Hartbrich·K. Hayasaka·H. Hayashii·M. T. Hedges·M. Hernandez Villanueva·W. -S. Hou·C. -L. Hsu·T. Iijima·G. Inguglia·A. Ishikawa·R. Itoh·M. Iwasaki·Y. Iwasaki·W. W. Jacobs·E. -J. Jang·S. Jia·Y. Jin·C. W. Joo·K. K. Joo·A. B. Kaliyar·K. H. Kang·G. Karyan·T. Kawasaki·C. H. Kim·D. Y. Kim·H. J. Kim·S. H. Kim·Y. -K. Kim·T. D. Kimmel·P. Kodyš·T. Konno·A. Korobov·S. Korpar·E. Kovalenko·P. Križan·R. Kroeger·P. Krokovny·M. Kumar·R. Kumar·K. Kumara·Y. -J. Kwon·K. Lalwani
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Abstract

We measure the branching fractions and $CP$ asymmetries for the decays $B^{0}\to \bar{D}^{0}\pi^{0}$ and $B^{+}\to \bar{D}^{0}\pi^{+}$, using a data sample of $772\times 10^{6}$ $B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^{+}e^{-}$ collider. The branching fractions obtained and direct $CP$ asymmetries are $\mathcal{B}(B^{0}\to \bar{D}^{0}\pi^{0}) = [2.70 \pm 0.06~ \text{(stat.)} \pm 0.10~ \text{(syst.)}] \times 10^{-4}$, $\mathcal{B}(B^{+}\to \bar{D}^{0}\pi^{+}) = [4.53 \pm 0.02~ \text{(stat.)} \pm 0.15~ \text{(syst.)}] \times 10^{-3}$, $ {\cal A}_{CP}(B^{0}\to \bar{D}^{0}\pi^{0}) = [+0.42 \pm 2.05~ \text{(stat.)} \pm 1.22~ \text{(syst.)}]\%$, and $ {\cal A}_{CP}(B^{+}\to \bar{D}^{0}\pi^{+}) = [+0.19 \pm 0.36~ \text{(stat.)} \pm 0.57~ \text{(syst.)}]\%$. The measurements of $\mathcal{B}$ are the most precise to date and are in good agreement with previous results, as is the measurement of ${\cal A}_{CP}(B^{+}\to \bar{D}^{0}\pi^{+})$. The measurement of ${\cal A}_{CP}$ for $B^{0}\to \bar{D}^{0}\pi^{0}$ is the first for this mode, and the value is consistent with Standard Model expectations.

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Belle Collaboration, T. Bloomfield, M. E. Sevior, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, J. Bennett, M. Bessner, T. Bilka, J. Biswal, A. Bobrov, G. Bonvicini, A. Bozek, M. Bračko, T. E. Browder, M. Campajola, L. Cao, D. Červenkov, M. -C. Chang, V. Chekelian, A. Chen, B. G. Cheon, K. Chilikin, H. E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, Y. Choi, S. Choudhury, D. Cinabro, S. Cunliffe, S. Das, N. Dash, G. De Nardo, R. Dhamija, F. Di Capua, Z. Doležal, T. V. Dong, S. Dubey, S. Eidelman, D. Epifanov, T. Ferber, D. Ferlewicz, B. G. Fulsom, R. Garg, V. Gaur, A. Garmash, A. Giri, P. Goldenzweig, C. Hadjivasiliou, S. Halder, O. Hartbrich, K. Hayasaka, H. Hayashii, M. T. Hedges, M. Hernandez Villanueva, W. -S. Hou, C. -L. Hsu, T. Iijima, G. Inguglia, A. Ishikawa, R. Itoh, M. Iwasaki, Y. Iwasaki, W. W. Jacobs, E. -J. Jang, S. Jia, Y. Jin, C. W. Joo, K. K. Joo, A. B. Kaliyar, K. H. Kang, G. Karyan, T. Kawasaki, C. H. Kim, D. Y. Kim, H. J. Kim, S. H. Kim, Y. -K. Kim, T. D. Kimmel, P. Kodyš, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, P. Križan, R. Kroeger, P. Krokovny, M. Kumar, R. Kumar, K. Kumara, Y. -J. Kwon, K. Lalwani. 2021-11-24. Measurement of the branching fraction and $CP$ asymmetry for $B\to\bar{D}^{0} \pi$ decays. https://doi.org/10.1103/physrevd.105.072007

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