$\epsilon'$ from right-handed currents

W. Dekens

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arXiv · 1708.00797

$\epsilon'$ from right-handed currents

W. Dekens

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Abstract

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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W. Dekens. 2017-08-02. $\epsilon'$ from right-handed currents. https://arxiv.org/abs/1708.00797

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