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arXiv · 1911.06554

A complete update of $\varepsilon'/\varepsilon$ in the Standard Model

V. Cirigliano·H. Gisbert·A. Pich·A. Rodríguez-Sánchez
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Abstract

The recent release of improved lattice data has revived again the interest on precise theoretical calculations of the direct CP-violation ratio $\varepsilon'/\varepsilon$. We present a complete update of the Standard Model prediction [1,2], including a new re-analysis of isospin-breaking corrections which are of vital importance in the theoretical determination of this observable. The Standard Model prediction, $\mathrm{Re} (\epsilon'/\epsilon) = (14\pm 5)\cdot 10^{-4}$, turns out to be in good agreement with the experimental measurement.

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V. Cirigliano, H. Gisbert, A. Pich, A. Rodríguez-Sánchez. 2019-11-15. A complete update of $\varepsilon'/\varepsilon$ in the Standard Model. https://arxiv.org/abs/1911.06554

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