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arXiv · 2207.07669

Electroweak Corrections to the Charm-Top-Quark Contribution to $\epsilon_K$

Joachim Brod·Sandra Kvedaraite·Zachary Polonsky·Ahmed Youssef
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Abstract

We calculate the leading-logarithmic and next-to-leading-logarithmic electroweak corrections to the charm-top-quark contribution to the effective $|\Delta S| = 2$ Lagrangian, relevant for the parameter $\epsilon_K$. We find that these corrections lead to a $-0.5\%$ shift in the corresponding Wilson coefficient. Moreover, our calculation removes an implicit ambiguity in the standard-model prediction of $\epsilon_K$, by fixing the renormalization scheme of the electroweak input parameters.

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Joachim Brod, Sandra Kvedaraite, Zachary Polonsky, Ahmed Youssef. 2022-07-15. Electroweak Corrections to the Charm-Top-Quark Contribution to $\epsilon_K$. https://doi.org/10.1007/jhep12(2022)014

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