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Two-loop electroweak contributions to $Δr$

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

A review is given on the quantum correction $Δr$ in the $W$--$Z$ mass correlation at the electroweak two-loop level, as derived from the calculation of the muon lifetime in the Standard Model. Exact results for $Δr$ and the $W$-mass prediction including ${\mathcal{O}}(α^2)$ 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. 2001-01-23. Two-loop electroweak contributions to $Δr$. https://arxiv.org/abs/hep-ph/0101260

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