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arXiv · hep-ph/9909436

Second Order Corrections to the Muon Lifetime and the Semileptonic B Decay

M. Steinhauser·T. Seidensticker
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Abstract

In this article two-loop QED corrections to the muon decay and corrections of order $α_s^2$ 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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M. Steinhauser, T. Seidensticker. 1999-09-20. Second Order Corrections to the Muon Lifetime and the Semileptonic B Decay. https://doi.org/10.1016/s0370-2693(99)01168-5

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