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 | 2023/01 |
形態種別 | その他 |
標題 | Measurement of the $B^{0} \rightarrow D^{*-} \ell^{+} ν_{\ell}$ branching ratio and $|V_{cb}|$ with a fully reconstructed accompanying $B$ meson in 2019-2021 Belle II data |
執筆形態 | その他 |
著者・共著者 | 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. Bhardw |
概要 | We present a measurement of the $B^{0} \rightarrow D^{*-} \ell^{+}
\nu_{\ell}$ ($\ell=e,\mu$) branching ratio and of the CKM parameter $|V_{cb}|$ using signal decays accompanied by a fully reconstructed $B$ meson. The Belle II data set of electron-positron collisions at the $\Upsilon(4S)$ resonance, corresponding to 189.3$\,$fb$^{-1}$ of integrated luminosity, is analyzed. With the Caprini-Lellouch-Neubert form factor parameterization, the parameters $\eta_{\rm EW} F(1) |V_{cb}|$ and $\rho^{2}$ are extracted, where $\eta_{\rm EW}$ is an electroweak correction, $F(1)$ is a normalization factor and $\rho^{2}$ is a form factor shape parameter. We reconstruct 516 signal decays and thereby obtain $\mathcal{B} (B^{0} \rightarrow D^{*-} \ell^{+} \nu_{\ell} ) = \left(5.27 \pm 0.22~\rm{\left(stat\right)} \pm 0.38~\rm{\left(syst\right)}\right) \%$, $\eta_{EW} F(1) |V_{cb}| \times 10^{3} = 34.6 \pm 1.8~\rm{\left(stat\right)} \pm 1.7~\rm{\left(syst\right)}$, and $\rho^{2} = 0.94 \pm 0.18~\rm{\left(stat\right)} \pm 0.11~\rm{\left(syst\right)}$. |
PermalinkURL | http://arxiv.org/abs/2301.04716v1 |
researchmap用URL | http://arxiv.org/pdf/2301.04716v1 |