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DOE OSTI · 1874435

Two-loop electroweak corrections to the Top-Quark Contribution to ϵ K

Brod, Joachim·Kvedaraitė, Sandra·Polonsky, Zachary
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Abstract

The parameter ϵ K measures CP violation in the neutral kaon system. It is a sensitive probe of new physics and plays a prominent role in the global fit of the Cabibbo-Kobabyashi-Maskawa matrix. The perturbative theory uncertainty is currently dominated by the top-quark contribution. Here, we present the calculation of the full two-loop electroweak corrections to the top-quark contribution to ϵ K , including the resummation of QED-QCD logarithms. We discuss different renormalization prescriptions for the electroweak input parameters. In the traditional normalization of the weak Hamiltonian with two powers of the Fermi constant G F , the top-quark contribution is shifted by –1%.

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Brod, Joachim, Kvedaraitė, Sandra, Polonsky, Zachary. 2021-12-28. Two-loop electroweak corrections to the Top-Quark Contribution to ϵ K. https://doi.org/10.1007/jhep12(2021)198

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