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Four-Loop Singlet Contribution to the $ρ$ Parameter

Y. Schroder·M. Steinhauser
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Abstract

We compute the four-loop contribution to the electroweak $ρ$ parameter induced by the singlet diagrams of the $Z$-boson self-energy. The numerical impact on the weak mixing angle and the $W$-boson mass is small.

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Y. Schroder, M. Steinhauser. 2005-11-11. Four-Loop Singlet Contribution to the $ρ$ Parameter. https://doi.org/10.1016/j.physletb.2005.06.085

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