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W. Dekens
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Recent lattice determinations of direct CP violation in kaon decays, parametrized by $epsilon$, suggest a discrepancy of several sigma between experiment and the standard model. Assuming that this situation is due to new physics, we investigate a solution in terms of right-handed charged currents. Chiral perturbation theory, in combination with lattice QCD results, allows one to accurately determine the effect of right-handed interactions on $epsilon$. In addition, similar techniques provide a direct link between the right-handed contributions to $epsilon$ and hadronic electric dipole moments. We demonstrate that the $epsilon$ discrepancy can be resolved with right-handed charged currents, and that this scenario can be falsified by next-generation hadronic electric dipole moment experiments.
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