quark mass dependence of the electromagnetic dipole operator contribution to B̄ → X s γ at O ( α 2 s )
نویسندگان
چکیده
We extend existing calculations of the electromagnetic dipole operator contribution to the total decay rate and the photon energy spectrum of the decay B̄ → Xsγ at O(αs) by working out the exact dependence on the charm quark mass.
منابع مشابه
QCD Contribution of the Electromagnetic Dipole Operator to Γ ( B̄ → X s γ )
We present an independent calculation of that part of the O(α 2 s) contribution to the decay width Γ(¯ B → X s γ) which arises from the self-interference term of the electromagnetic dipole operator O 7. Using a different method, we find complete agreement with a previous calculation. This NNLL contribution is an important ingredient for the complete NNLL prediction of Γ(¯ B → X s γ) which will ...
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