Extraction of |Vcb| from B \u2192 D(\u2217)\u2113\u03bd\u2113 and the Standard Model predictions of R(D(\u2217))

Abstract

We extract |Vcb| from the available data in the decay B → D(∗)ℓνℓ. B → D∗ℓνℓ, the unfolded binned differential decay rates of four kinematic variables including the q2 bins have been used. In the CLN and BGL parameterizations of the form factors, the combined fit to all the available data along with their correlations yields |Vcb| = (39.77 ± 0.89) × 10−3 and (40.90 ± 0.94) × 10−3 respectively. In these fits, we have used the inputs from lattice and light cone sum rule (LCSR) along with the data. Using our fit results and the HQET relations (with the known corrections included) amongst the form factors, and parameterizing the unknown higher order corrections (in the ratios of HQET form factors) with a conservative estimate of the normalizing parameters, we obtain R(D∗) = 0.259 ± 0.006 (CLN) and R(D∗) = 0.257 ± 0.005 (BGL).