Next-to-leading order QCD corrections to the form factors of B to scalar meson decays

Abstract

We calculate the next-to-leading order QCD corrections to B to scalar meson form factors from QCD light-cone sum rules with B meson light-cone distribution amplitudes. We demonstrate that the B meson-to-vacuum correlation functions can be factorized into the convolution of short-distance coefficients and light-cone distribution amplitudes at the one-loop level and find that only $$ {\phi}_B^{+} $$ ϕ B + (ω, μ) contributes to the form factors. We then employ the z-parameterization combined with constraints from strong coupling constants to reconstruct the q2 dependence of the form factors in the whole kinematic allowed regions. Due to the large cancellations between the hard functions and the jet functions, the next-to-leading order results show a modest increase of approximately 5% compared to the leading order results. Based on the results of form factors, we predict the branching ratios of semi-leptonic B → $$ S\ell {\overline{\nu}}_{\ell } $$ S ℓ ν ¯ ℓ and B → $$ S{\nu}_{\ell }{\overline{\nu}}_{\ell } $$ S ν ℓ ν ¯ ℓ processes, as well as several angular observables, such as forward-backward asymmetries, “flat terms” and lepton polarization asymmetries. We compare these results with calculations from other methods. Experimental verification of these results is required in future experiments.

Decay constants of $$ c\overline{b} $$ mesons involving the ten heavy flavor-changing currents at N3LO QCD

“…Within the QCD sum rules, the S-wave and P -wave light meson decay constants involving the scalar, vector, axial-vector, tensor and axial-tensor currents were calculated in the literature [20, 25-28, 36-48, 70, 85-92], the S-wave and P -wave heavy-light meson decay constants involving the scalar, axial-vector, tensor and axial-tensor currents can be found in refs. [49][50][51][52], the P -wave heavy quarkonium decay constants coupled with the tensor and axial-tensor currents were studied in the literature [93], and the P -wave B * c0 and B c1 decay constants coupled with the scalar and axial-vector currents can be obtained from refs. [53,[94][95][96][97].…”