新山 雅之 所属 京都産業大学 理学部 物理科学科 職種 教授 |
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発行・発表の年月 | 2022/06 |
形態種別 | その他 |
標題 | Study of Exclusive $B \to πe^+ ν_e$ Decays with Hadronic Full-event-interpretation Tagging in 189.3 fb$^{-1}$ of Belle II Data |
執筆形態 | その他 |
著者・共著者 | 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, |
概要 | We present a reconstruction of the semileptonic decays $B^0 \to \pi^- e^+
\nu_e$ and $B^+ \to \pi^0 e^+ \nu_e$ in a sample corresponding to 189.3 fb$^{-1}$ of Belle II data, using events where the partner $B$-meson is reconstructed from a large variety of hadronic channels via a tagging algorithm known as the full-event-interpretation. We determine the partial branching fractions in three bins of the squared momentum transfer to the leptonic system using fits to the distribution of the square of the missing mass. The partial branching fractions are summed to determine $\mathcal{B}(B^0 \to \pi^- e^+ \nu_e)$ = (1.43 $\pm$ 0.27(stat) $\pm$ 0.07(syst)) $\times 10^{-4}$ and $\mathcal{B}(B^+ \to \pi^0 e^+ \nu_e)$ = (8.33 $\pm$ 1.67(stat) $\pm$ 0.55(syst)) $\times 10^{-5}$. We extract a first Belle II measurement of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element $|V_{\mathrm{ub } }|$, with $|V_{\mathrm{ub } }|$ = (3.88 $\pm$ 0.45) $\times 10^{-3}$. |
PermalinkURL | http://arxiv.org/abs/2206.08102v2 |
researchmap用URL | http://arxiv.org/pdf/2206.08102v2 |