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Two-loop renormalization of the electric charge in the Standard Model

Giuseppe Degrassi·Alessandro Vicini
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Abstract

We discuss the renormalization of the electric charge at the two-loop level in the Standard Model of the electroweak interactions. We explicitly calculate the expression of the complete on-shell two-loop counterterm using the Background Field Method and discuss the advantages of this computational approach. We consider the related quantity $\hat e(μ)$, defined in the $\ms$ renormalization scheme and present numerical results for different values of the scale $μ$. We find that the full 2-loop electroweak corrections contribute more than 10 parts in units $10^{-5}$ to the $Δ\hatα(\mz^2)$ parameter, obtaining $\hatα^{-1}(\mz)= 128.12 \pm 0.05$ for $Δα_{had}(\mz^2) =0.027572 \pm 0.000359$.

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Giuseppe Degrassi, Alessandro Vicini. 2004-02-16. Two-loop renormalization of the electric charge in the Standard Model. https://doi.org/10.1103/physrevd.69.073007

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