Heavy-to-light form factors: Symmetries at large recoil and calculation of alpha_s corrections

Abstract

Recently it has been shown that in the large-recoil limit new symmetries emerge which impose various relations on form factors that parametrise the decay of heavy B mesons into light mesons. These symmetry relations are broken by radiative QCD corrections. We show that these corrections are perturbatively calculable, and present results to first order in the strong coupling constant alpha_s.