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arXiv · hep-ph/9807399

Soft Superweak CP Violation and the Strong CP Puzzle

Howard Georgi·Sheldon L. Glashow
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Abstract

We discuss a class of models in which CP is violated softly in a heavy sector adjoined to the standard model. Heavy-sector loops produce the observed CP violation in kaon physics, yielding a tiny and probably undetectable value for $ε^\prime$. All other CP-violating parameters in the effective low-energy standard model, including the area of the unitarity triangle and $\barθ$, are finite, calculable and can be made very small. The leading contribution to $\barθ$ comes from a four-loop graph. These models offer a natural realization of superweak CP violation and can resolve the strong CP puzzle. In one realization of this idea, CP is violated in the mass matrix of heavy majorana neutrinos.

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Howard Georgi, Sheldon L. Glashow. 1999-02-12. Soft Superweak CP Violation and the Strong CP Puzzle. https://doi.org/10.1016/s0370-2693(99)00246-4

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