B̄\ → Xₛγ in the Two Higgs Doublet Model up to next-to-next-to-leading order in QCD

A bstract We compute three-loop matching corrections to the Wilson coefficients C 7 and C 8 in the Two Higgs Doublet Model by applying expansions for small, intermediate and large charged Higgs boson masses. The results are used to evaluate the branching ratio of B̄\ → Xₛγ to next-to-next-to leading order accuracy, and to determine an updated lower limit on the charged Higgs boson mass. We find M H + ≥ 380GeV at 95% confidence level when the recently completed BABAR data analysis is taken into account. Our results for the charged Higgs contribution to the branching ratio exhibit considerably weaker sensitivity to the matching scale μ 0 , as compared to previous calculations.