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Isospin violation in epsilon'

V. Cirigliano·A. Pich·G. Ecker·H. Neufeld
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Abstract

On the basis of a next-to-leading-order calculation in chiral perturbation theory, the first complete analysis of isospin breaking for direct CP violation in K^0 -> 2 pi decays is performed. We find a destructive interference between three different sources of isospin violation in the CP violation parameter epsilon'. Within the uncertainties of large-N_c estimates for the low-energy constants, the isospin violating correction for epsilon' is below 15 %.

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V. Cirigliano, A. Pich, G. Ecker, H. Neufeld. 2003-07-02. Isospin violation in epsilon'. https://doi.org/10.1103/physrevlett.91.162001

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