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arXiv · 2404.16945

Seesaw Limit of the Nelson-Barr Mechanism

A. L. Cherchiglia·A. G. Dias·J. Leite·C. C. Nishi
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Abstract

We investigate how the solution to the strong CP problem and the explanation for the observed fermion mass hierarchies can be intrinsically related. Specifically, we explore the Nelson-Barr mechanism and identify its "seesaw limit", where light quark masses are suppressed by large CP-violating terms. Upon adding three (two) vector-like quarks that mix with the down-type (up-type) quark sector of the Standard Model, we demonstrate how the lack of CP violation in the strong sector and the observed quark mass hierarchy can be simultaneously achieved.

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A. L. Cherchiglia, A. G. Dias, J. Leite, C. C. Nishi. 2024-04-25. Seesaw Limit of the Nelson-Barr Mechanism. https://arxiv.org/abs/2404.16945

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