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 2021/11
形態種別 その他
標題 Exclusive $B \to X_u \ell ν_\ell$ Decays with Hadronic Full-event-interpretation Tagging in 62.8 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,R. Adak,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. Beaulieu,J. Becker,P. K. Behera,J. V. Bennett,E. Bernieri,F. U. Bernlochner,M. Bertemes,E. Bertholet,M. Bessner,S. Bet
概要 We present a reconstruction in early data of the semileptonic decay $B^+ \to
\pi^0 \ell^+ \nu_\ell$, and first results of a reconstruction of the decays
$B^+ \to \rho^0 \ell^+ \nu_\ell$ and $B^0 \to \rho^- \ell^+ \nu_\ell$ in a
sample corresponding to 62.8 fb$^{-1}$ of Belle II data using hadronic
$B$-tagging via the full-event-interpretation algorithm. We determine the total
branching fractions via fits to the distribution of the square of the missing
mass, and find $\mathcal{B}(B^+ \to \pi^0 \ell^+ \nu_\ell)$ = (8.29 $\pm$
1.99(stat) $\pm$ 0.46(syst)) $\times 10^{-5}$. We obtain $95\%$ CL upper limits
on the branching fractions with $\mathcal{B}(B^0 \to \rho^- \ell^+ \nu_\ell) <
3.37 \times 10^{-4}$ and $\mathcal{B}(B^+ \to \rho^0 \ell^+ \nu_\ell) < 19.7
\times 10^{-5}$. We also obtain an updated branching fraction for the $B^0 \to
\pi^- \ell^+ \nu_\ell$ decay, $\mathcal{B}(B^0 \to \pi^- \ell^+ \nu_\ell)$ =
(1.47 $\pm$ 0.29(stat) $\pm$ 0.05(syst)) $\times 10^{-4}$, based on the sum of
the partial branching fractions in three bins of the squared momentum transfer
to the leptonic system.
PermalinkURL http://arxiv.org/abs/2111.00710v1
researchmap用URL http://arxiv.org/pdf/2111.00710v1