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The effective electroweak mixing angle $\sin^2θ_{eff}$ with two-loop fermionic contributions

W. Hollik·U. Meier·S. Uccirati
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Abstract

We present the results from a calculation of the full electroweak two-loop fermionic contributions to the effective leptonic mixing angle of the $Z$ boson, $\sin^2θ_{eff}$, in the Standard Model. On-shell renormalization and analytic calculations are performed for the three-point vertex functions at zero external momenta, whereas irreducible three-point integrals for non-vanishing external momenta are evaluated semi-analytically applying two different methods. Comparisons with a previous calculation show complete agreement.

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W. Hollik, U. Meier, S. Uccirati. 2005-10-20. The effective electroweak mixing angle $\sin^2θ_{eff}$ with two-loop fermionic contributions. https://doi.org/10.1016/j.nuclphysb.2005.10.015

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