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arXiv · hep-ph/0007129

Calculation of fermionic two-loop contributions to muon decay

A. Freitas·S. Heinemeyer·W. Hollik·W. Walter·G. Weiglein
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Abstract

The computation of the correction Δr 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 γ_5. Exact results for Δr and the W mass prediction including O(α^2) corrections with fermion loops are presented and compared with previous results of a next-to-leading order expansion in the top-quark mass.

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A. Freitas, S. Heinemeyer, W. Hollik, W. Walter, G. Weiglein. 2000-08-11. Calculation of fermionic two-loop contributions to muon decay. https://doi.org/10.1016/s0920-5632(00)00827-6

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