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Epsilon'/Epsilon in the Standard Model: Theoretical Update

A. Pich
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Abstract

A complete analysis of isospin breaking in K to 2 pion amplitudes, including both strong and electromagnetic corrections at next-to-leading order in chiral perturbation theory, has been achieved recently.We discuss the implication of these effects, together with the previously known chiral loop corrections, on the direct CP-violating ratio epsilon'/epsilon. One finds Re(epsilon'/epsilon) = (19^{+11}_{-9}) 10^{-4}.

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A. Pich. 2004-10-14. Epsilon'/Epsilon in the Standard Model: Theoretical Update. https://arxiv.org/abs/hep-ph/0410215

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