We determine the Cabibbo-Kobayashi-Maskawa matrix-element magnitude |Vcb| using ¯B0→D*+ℓ−¯νℓ decays reconstructed in 189 fb−1 of collision data collected by the Belle II experiment, located at the SuperKEKB e+e− collider. Partial decay rates are reported as functions of the recoil parameter w and three decay angles separately for electron and muon final states. We obtain |Vcb| using the Boyd-Grinstein-Lebed and Caprini-Lellouch-Neubert parametrizations, and find |Vcb|BGL=(40.57±0.31±0.95±0.58)×10−3 and |Vcb|CLN=(40.13±0.27±0.93±0.58)×10−3 with the uncertainties denoting statistical components, systematic components, and components from the lattice QCD input, respectively. The branching fraction is measured to be B(¯B0→D*+ℓ−¯νℓ)=(4.922±0.023±0.220)%. The ratio of branching fractions for electron and muon final states is found to be 0.998±0.009±0.020. In addition, we determine the forward-backward angular asymmetry and the D*+ longitudinal polarization fractions. All results are compatible with lepton-flavor universality in the Standard Model.
Adachi, I., Aggarwal, L., Ahmed, H., Aihara, H., Akopov, N., Aloisio, A., et al. (2023). Determination of |Vcb| using B¯0→D*+ℓ−ν¯ℓ decays with Belle II. PHYSICAL REVIEW D, 108(9), 092013-1-092013-26 [10.1103/PhysRevD.108.092013].
Determination of |Vcb| using B¯0→D*+ℓ−ν¯ℓ decays with Belle II
Branchini, P.Membro del Collaboration Group
;Budano, A.Membro del Collaboration Group
;Bussino, S.Membro del Collaboration Group
;De Pietro, G.Membro del Collaboration Group
;Laurenza, M.Membro del Collaboration Group
;Martellini, C.Membro del Collaboration Group
;Martini, A.Membro del Collaboration Group
;
2023-01-01
Abstract
We determine the Cabibbo-Kobayashi-Maskawa matrix-element magnitude |Vcb| using ¯B0→D*+ℓ−¯νℓ decays reconstructed in 189 fb−1 of collision data collected by the Belle II experiment, located at the SuperKEKB e+e− collider. Partial decay rates are reported as functions of the recoil parameter w and three decay angles separately for electron and muon final states. We obtain |Vcb| using the Boyd-Grinstein-Lebed and Caprini-Lellouch-Neubert parametrizations, and find |Vcb|BGL=(40.57±0.31±0.95±0.58)×10−3 and |Vcb|CLN=(40.13±0.27±0.93±0.58)×10−3 with the uncertainties denoting statistical components, systematic components, and components from the lattice QCD input, respectively. The branching fraction is measured to be B(¯B0→D*+ℓ−¯νℓ)=(4.922±0.023±0.220)%. The ratio of branching fractions for electron and muon final states is found to be 0.998±0.009±0.020. In addition, we determine the forward-backward angular asymmetry and the D*+ longitudinal polarization fractions. All results are compatible with lepton-flavor universality in the Standard Model.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
