B → Dlνl form factors beyond leading power and extraction of |Vcb| and R(D)

We investigate the subleading-power corrections to the exclusive B -> Dl nu(l) form factors at O(alpha(0)(s)) in the light-cone sum rules (LCSR) framework by including the two- and three-particle higher-twist contributions from the B-meson light-cone distribution amplitudes up to the twist-six accuracy, by taking into account the subleading terms in expanding the hard-collinear charm-quark propagator, and by evaluating the hadronic matrix element of the subleading effective current (q) over bar gamma(mu) i(sic)(perpendicular to)/(2m(b))h(v). Employing further the available leading-power results for the semileptonic B -> D form factors at the next-to-leading-logarithmic level and combining our improved LCSR predictions with the recent lattice determinations, we then carry out a comprehensive phenomenological analysis on the semi-leptonic B -> Dl nu(l) decay. We extract vertical bar V-cb vertical bar = (40.2(-0.5)(+0.6)vertical bar (+1.4)(th-1.4)vertical bar(exp) X 10(-3) vertical bar V-cb vertical bar = (40.9(-0.5)(+0.6)vertical bar(th) (+1.0)(-1.0)vertical bar(exp)) x 10(-3)) using the BaBar (Belle) experimental data, and particularly obtain for the gold-plated ratio R(D) = 0.302 +/- 0.003.

Automated summary

In this study, we investigate the subleading-power corrections to the form factors of the exclusive B -> Dl nu(l) decay. We utilize the light-cone sum rules (LCSR) framework and consider the two- and three-particle higher-twist contributions as well as the subleading terms. By combining our improved LCSR predictions with recent lattice determinations, we conduct a comprehensive phenomenological analysis and obtain important results for the semi-leptonic B -> Dl nu(l) decay.