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 | 2020/09 |
形態種別 | その他 |
標題 | Measurement of Hadronic Mass Moments $\langle M_X^n \rangle $ in $B \rightarrow X_c \ell ν$ Decays at Belle II |
執筆形態 | その他 |
著者・共著者 | Belle II Collaboration,F. Abudinén,I. Adachi,R. Adak,K. Adamczyk,P. Ahlburg,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,S. Baehr,S. Bahinipati,A. M. Bakich,P. Bambade,Sw. Banerjee,S. Bansal,M. Barrett,G. Batignani,J. Baudot,A. Beaulieu,J. Becker,P. K. Behera,M. Bender,J. V. Bennett,E. Bernieri,F. U. Bernlochner,M. Bertemes,M. Bessner,S. Bettarini,V. Bhardwaj,B. Bhuyan,F. Bianchi,T. Bilka |
概要 | We present measurements of the first six hadronic mass moments in
semileptonic $B \rightarrow X_c \ell \nu $ decays. The hadronic mass moments, together with other observables of inclusive $B$ decays, can be used to determine the CKM matrix element $|{V_{cb } }|$ and mass of the $b$-quark $m_b$ in the context of Heavy Quark Expansions of QCD. The Belle~II data recorded at the $\Upsilon (4S)$ resonance in 2019 and 2020 (March-July), corresponding to an integrated luminosity of $34.6\;\mathrm{fb}^{-1}$, is used for this measurement. The decay $\Upsilon (4S) \rightarrow B \overline{B}$ is reconstructed by applying the hadronic tagging algorithm provided by the Full Event Interpretation to fully reconstruct one $B$ meson. The second $B$ meson is reconstructed inclusively by selecting a high-momentum lepton. The $X_c$ system is identified by the remaining reconstructed tracks and clusters in the electromagnetic calorimeter. We report preliminary results for the hadronic mass moments $\langle M_X^n \rangle $ with $n=1,\dots,6$, measured as a function of a lower cut on the lepton momentum in the signal $B$ rest frame. |
PermalinkURL | http://arxiv.org/abs/2009.04493v1 |
researchmap用URL | http://arxiv.org/pdf/2009.04493v1 |