Semileptonic decays B/Bs → (π, k)(l+l-, lv, v(v)over-bar) in the perturbative QCD approach beyond the leading order

In this paper we first calculate the form factors of B -> (pi, K) and B-s -> K transitions by employing the perturbative QCD (pQCD) factorization approach with the inclusion of the next-to-leading-order (NLO) corrections, and then we calculate the branching ratios of the corresponding semileptonic decays B/B-s -> (pi, K)(l(+)l(-), lv; v (v) over bar) (here l denotes e, mu, and tau). Based on the numerical calculations and phenomenological analysis, we find the following results: (a) For B -> (pi, K) and B-s -> K transition form factors F-0,F-+,F-T(q(2)), the NLO pQCD predictions for the values of F-0,F-+,F-T(0) and their q(2) dependence agree well with those obtained from other methods; (b) for (B) over bar (0) -> pi(+)l(-)(v) over bar (l), (K) over bar (0)l(+)l(-) and B- -> pi(0)l(-)(v) over bar (l), K(-)l(+)l(-) decay modes, the NLO pQCD predictions for their branching ratios agree very well with the measured values; (c) by comparing the pQCD predictions for Br((B) over bar (0) -> pi(+)l-(v) over bar (l)) with the measured decay rate, we extract out the magnitude of V-ub: vertical bar V-ub vertical bar (3.80(-0.60)(+0.66)(theor) +/- 0.13) x 10(-3); (d) we also define several ratios of the branching ratios, R-v, R-C and R-N1,R-N2,R-N3, and present the corresponding pQCD predictions, which will be tested by LHCb and the forthcoming Super-B experiments. DOI: 10.1103/PhysRevD.86.114025