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Two-loop contributions to electroweak precision observables in the MSSM

J. Haestier·D. Stöckinger·G. Weiglein·S. Heinemeyer
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Abstract

The evaluation of the two-loop MSSM-contributions to the electroweak precision observables M_W and s_w^eff at order(alpha_t^2), order(alpha_t alpha_b), order(alpha_b^2) is presented. These contributions enter via Delta(rho), and it is explained in detail how one can retain the true, non-vanishing value of the MSSM Higgs boson mass M_h in spite of using the gauge-less limit in the calculation. The numerical results can be sizeable, in particular for strong squark mixing. By comparing the results in the on-shell and DR-bar renormalization schemes, the remaining theoretical uncertainty is found to be small.

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J. Haestier, D. Stöckinger, G. Weiglein, S. Heinemeyer. 2005-07-01. Two-loop contributions to electroweak precision observables in the MSSM. https://arxiv.org/abs/hep-ph/0506259

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