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 2023/04
形態種別 その他
標題 Novel method for the identification of the production flavor of neutral charmed mesons
執筆形態 その他
著者・共著者 Belle II Collaboration,I. Adachi,L. Aggarwal,H. Ahmed,H. Aihara,N. Akopov,A. Aloisio,N. Anh Ky,D. M. Asner,H. Atmacan,T. Aushev,V. Aushev,M. Aversano,V. Babu,H. Bae,S. Bahinipati,P. Bambade,Sw. Banerjee,M. Barrett,J. Baudot,M. Bauer,A. Baur,A. Beaubien,J. Becker,P. K. Behera,J. V. Bennett,F. U. Bernlochner,V. Bertacchi,M. Bertemes,E. Bertholet,M. Bessner,S. Bettarini,B. Bhuyan,F. Bianchi,T. Bilka,D. Biswas,A. Bobrov,D. Bodrov,A. Bolz,A. Bondar,J. Borah,A. Bozek,M. Bračko,P. Branchini,R. A. Brier
概要 We propose a new algorithm for the identification of the production flavor of
neutral $D$ mesons in the Belle II experiment. The algorithm exploits the
correlation between the flavor of a reconstructed neutral $D$ meson (signal $D$
meson) and the electric charges of particles reconstructed in the rest of the
$e^+e^-\to c \bar{c}$ event. These include those originating from the decay of
the other charm hadron produced in the event, as well as those possibly
produced in association with the signal $D$ meson. We develop the algorithm
using simulation and calibrate it in data using decay modes that identify the
flavor of the decaying neutral $D$ meson. We use a data sample of $e^+e^-$
collisions, corresponding to $362\,\mathrm{fb}^{-1}$ of integrated luminosity,
collected by Belle II at center-of-mass energies near the $\Upsilon(4S)$ mass.
The effective tagging efficiency in data is $(47.91 \pm 0.07 \mathrm{(stat)}
\pm 0.51 \mathrm{(syst)})\%$, independent of the neutral-$D$-meson decay mode.
This charm flavor tagger will approximately double the effective sample size of
many $CP$-violation and charm-mixing measurements that so far have exclusively
relied on neutral $D$ mesons originating from $D^{*\pm}$ decays. While
developed for Belle II, the basic principles underlying the charm flavor tagger
can be used in other experiments, including those at hadron colliders.
DOI 10.1103/PhysRevD.107.112010
PermalinkURL http://arxiv.org/abs/2304.02042v2
researchmap用URL http://arxiv.org/pdf/2304.02042v2