新山　雅之
   所属   京都産業大学  理学部 物理科学科
   職種   教授
発行・発表の年月 2022/10
形態種別 その他
標題 Determination of $|V_{cb}|$ from $B\to D\ellν$ decays using 2019-2021 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 determination of the magnitude of the Cabibbo-Kobayashi-Maskawa
(CKM) matrix element $V_{cb}$ using $B\to D\ell\nu$ decays. The result is based
on $e^+e^-\to\Upsilon(4S)$ data recorded by the Belle II detector corresponding
to 189.2/fb of integrated luminosity. The semileptonic decays $B^0\to D^-(\to
K^+\pi^-\pi^-)\ell^+\nu_\ell$ and $B^+\to\bar D^0(\to K^+\pi^-)\ell^+\nu_\ell$
are reconstructed, where $\ell$ is either electron or a muon. The second $B$
meson in the $\Upsilon(4S)$ event is not explicitly reconstructed. Using the
diamond-frame method, we determine the $B$ meson four-momentum and thus the
hadronic recoil. We extract the partial decay rates as functions of $w$ and
perform a fit to the decay form-factor and the CKM parameter $|V_{cb}|$ using
the BGL parameterization of the form factor and lattice QCD input from the
FNAL/MILC and HPQCD collaborations. We obtain $\eta_{EW}|V_{cb}|=(38.53\pm
1.15)\times 10^{-3}$, where $\eta_{EW}$ is an electroweak correction, and the
error accounts for theoretical and experimental sources of uncertainty.
PermalinkURL http://arxiv.org/abs/2210.13143v1
researchmap用URL http://arxiv.org/pdf/2210.13143v1