2020/09/09 by Belle II Collaboration, Abudinén, F., Adachi, I. +540
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex)
paper · doi:10.48550/arxiv.2009.04493
We present measurements of the first six hadronic mass moments in semileptonic B → Xc ℓ ν decays. The hadronic mass moments, together with other observables of inclusive B decays, can be used to determine the CKM matrix element |Vcb| and mass of the b-quark mb in the context of Heavy Quark Expansions of QCD. The Belle~II data recorded at the Υ(4S) resonance in 2019 and 2020 (March-July), corresponding to an integrated luminosity of 34.6 fb-1, is used for this measurement. The decay Υ(4S) → B 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 Xc system is identified by the remaining reconstructed tracks and clusters in the electromagnetic calorimeter. We report preliminary results for the hadronic mass moments ⟨ MXn ⟩ with n=1,…,6, measured as a function of a lower cut on the lepton momentum in the signal B rest frame.