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arXiv · hep-ph/9705345

QCD Corrections to $b\to sγγ$ and Exclusive $B_s\to γγ$ Decay

Chia-Hung V. Chang·Guey-Lin Lin·York-Peng Yao
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Abstract

The short distance QCD corrections to $b\to sγγ$ 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 $B_s\to γγ$ decay. The branching ratio of this decay is found to be $5\times 10^{-7}$ in the Standard Model. We also found that QCD corrections modify considerably the ratio between CP-even and CP-odd two-photon amplitudes.

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Chia-Hung V. Chang, Guey-Lin Lin, York-Peng Yao. 1997-08-23. QCD Corrections to $b\to sγγ$ and Exclusive $B_s\to γγ$ Decay. https://doi.org/10.1016/s0370-2693(97)01208-2

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