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arXiv · hep-ph/0305248

Complete Two Loop Electroweak Contributions to the Muon Lifetime in the Standard Model

M. Awramik·M. Czakon
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Abstract

An independent result for the two loop fermionic contributions to the muon lifetime in the Standard Model is obtained. Deviations are found with respect to \cite{Freitas:2000gg}, which result in a shift of the W boson mass by approximately -1.3 MeV over the range of Higgs boson masses from 100 GeV to 1 TeV. Supplied with the bosonic contributions from \cite{Awramik:2002wn,Onishchenko:2002ve,Awramik:2002vu}, this shift, due to the complete electroweak contributions, varies from -2.4 MeV to -0.6 MeV. Additionally, a new test of the matching procedure defining the Fermi constant is presented, which uses fermion masses as infrared regulators.

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M. Awramik, M. Czakon. 2003-05-26. Complete Two Loop Electroweak Contributions to the Muon Lifetime in the Standard Model. https://doi.org/10.1016/j.physletb.2003.06.007

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