Symmetry-breaking corrections to heavy-to-light B meson form factors at large recoil

Recently it has been shown that symmetries emerging in the heavy quark and large recoil energy limit impose various relations on form factors that parametrise the decay of B mesons into light mesons. These symmetries are broken by perturbative effects. In this paper we discuss the structure of heavy-to-light form factors including such effects and compute symmetry-breaking corrections to first order in the strong coupling. As an application of our results we consider the forwardbackward asymmetry zero in the rare decay B → V l+l− and the possibility to constrain potential new physics contributions to the Wilson coefficient C9. (submitted to Nucl. Phys. B)