Two-loop QCD corrections to charged-Higgs-mediated b → sγ decay Original Research Article

The charged-Higgs-mediated contribution to the Wilson coefficient of the b → sγ magnetic penguin is expected to be one of the more promising candidates for a supersymmetric effect in B physics, probably the only one in gauge-mediated models. We compute the two-loop QCD correction to it. With naïve dimensional regularization and MS subtraction, for reasonable values of the charged Higgs mass and for μ = mt, we find a (10–20)% reduction of the corresponding one-loop effect.