Calculation of fermionic two-loop contributions to muon decay∗
نویسندگان
چکیده
The computation of the correction ∆r in the W-Z mass correlation, derived from muon decay, is described at the two-loop level in the Standard Model. Technical aspects which become relevant at this level are studied, e.g. gauge-parameter independent mass renormalization, ghost-sector renormalization and the treatment of γ5. Exact results for ∆r and the W mass prediction including O(α2) corrections with fermion loops are presented and compared with previous results of a next-to-leading order expansion in the top-quark mass. Talk given by A. F. at the 5th Zeuthen Workshop on Elementary Particle Theory ”Loops and Legs in Quantum Field Theory”, Bastei/Königstein, Germany, April 9–14, 2000
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تاریخ انتشار 2000