Radiative B Decay in the SM

Abstract

The experimental and theoretical status of the inclusive decay B -> X_s gamma is briefly summarized. Results from a very recent theoretical analysis are reported. An ~11% increase in the SM prediction for BR[ B -> X_s gamma] is found after replacing m_c^pole/m_b^pole by m_c(mu)/m_b^1S in the NLO QCD correction. The well-known enhancement of the branching ratio by QCD logarithms is identified as an effect of m_b-evolution in the top-quark contribution to the amplitude. This observation helps controlling the residual scale-dependence. The present prediction for the "total" branching ratio differs by 1.4 sigma from the experimental world average.

Comments: Contribution to the proceedings of the XXXVIth Rencontres de Moriond, Les Arcs, March 2001. 4 pages, 2 figures, uses epsfig