Second Order Corrections to the Muon Lifetime and the Semileptonic B Decay
نویسنده
چکیده
In this article two-loop QED corrections to the muon decay and corrections of order αs to the semileptonic decay of the bottom quark are considered. We compute the imaginary part of the four-loop diagrams contributing to the corresponding fermion propagator in the limit of small external momentum. The on-shell condition is obtained with the help of a conformal mapping and Padé approximation. Via this method we confirm the existing results by an independent calculation.
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