/ 97 06 25 3 v 1 5 J un 1 99 7 QCD corrections to b → sγγ induced decays : B → X s γγ and B s → γγ
نویسندگان
چکیده
We present a complete calculation of the Leading Order QCD corrections to the quark level decay amplitude for b → sγγ and study their relevance for both the inclusive branching ratio BR(B → Xsγγ) and for the exclusive decay channel Bs → γγ. In addition to the uncertainties in the short distance calculation, due to the choice of the renormalization scale, an appreciable uncertainty in both Bs → γγ and B → Xsγγ is introduced by the matrix element calculation. We also briefly discuss some long distance effects, especially those due to the ηc resonance for the inclusive rate. Finally, a brief analysis of the IR singularities of the two photon spectrum in the inclusive case is given.
منابع مشابه
QCD Corrections to b → sγγ and Exclusive B s → γγ decay
The short distance QCD corrections to b → sγγ are calculated in the leading logarithmic approximation. The equivalence of operator basis reduction for S-matrix elements by using the equations of motion or by proving a low energy theorem is discussed. We apply the above results to the exclusive Bs → γγ decay. The branching ratio of this decay is found to be 5 × 10 in the Standard Model. We also ...
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