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Higgs-mass dependence of the effective electroweak mixing angle $\sin^2θ_{eff}$ at the two-loop level

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

The result for the Higgs-dependent electroweak two-loop bosonic contributions to the effective leptonic mixing angle of the $Z$-boson in the Standard Model is presented. Together with the previously calculated fermionic contributions it yields the complete dependence of $\sin^2θ_{\rm eff}$ on the Higgs-boson mass $M_H$. Compared to the fermionic contributions, the bosonic contributions are found to be smaller and have the opposite sign, compensating part of the fermionic contributions.

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W. Hollik, U. Meier, S. Uccirati. 2005-11-18. Higgs-mass dependence of the effective electroweak mixing angle $\sin^2θ_{eff}$ at the two-loop level. https://doi.org/10.1016/j.physletb.2005.11.032

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