B -> pi, B(s) -> K form factors and Vub determination

TL;DR

This paper uses QCD light-cone sum rules with next-to-leading order corrections to estimate B -> pi, B -> K, and Bs -> K form factors, incorporating SU(3) symmetry breaking and providing a new determination of Vub.

Contribution

It introduces an improved LCSR calculation with MS-bar b-quark mass and includes SU(3) breaking effects, refining form factor and Vub estimates.

Findings

Calculated form factors with radiative corrections.

Included SU(3) symmetry breaking effects.

Provided a new Vub CKM matrix element estimate.

Abstract

We present a QCD light-cone sum rule (LCSR) estimation of the B -> pi, B -> K, and Bs -> K form factors calculating gluon radiative corrections at next-to-leading order. The MS-bar b-quark mass is used, instead of the one-loop pole mass employed in the previous analyses. For B -> K and Bs -> K form factors the SU(3)-symmetry breaking corrections are included, both in the hard-scattering kernels and in the distribution amplitudes (DAs). By combining the predicted value for f^+_{Bpi}(0) with the product |Vub f^+_{Bpi}| extracted from the B -> pi l nu measurement, we obtain the LCSR prediction for Vub CKM matrix element.