Measurement of differential distributions of B →d∗ℓ ν ¯ ℓ and implications on
We present a measurement of the differential shapes of exclusive B→D∗ℓν¯ℓ (B=B-,B¯0 and ℓ=e, μ) decays with hadronic tag-side reconstruction for the full 711 fb-1 Belle dataset. We extract the Caprini-Lellouch-Neubert (CLN) and Boyd-Grinstein-Lebed (BGL) form factor parameters and use an external input for the absolute branching fractions to determine the Cabibbo-Kobayashi-Maskawa matrix element and find |Vcb|CLN=(40.2±0.9)×10-3 and |Vcb|BGL=(40.7±1.0)×10-3 with the zero-recoil lattice QCD point F(1)=0.906±0.013. We also perform a study of the impact of beyond zero-recoil lattice QCD calculations on the |Vcb| determinations. Additionally, we present the lepton-flavor universality ratio Reμ=B(B→D∗eν¯e)/B(B→D∗μν¯μ)=0.993±0.023±0.023, the electron and muon forward-backward asymmetry and their difference ΔAFB=0.028±0.028±0.008, and the electron and muon D∗ longitudinal polarization fraction and their difference ΔFLD∗=0.030±0.025±0.007. The uncertainties quoted correspond to the statistical and systematic uncertainties, respectively.
