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arXiv · 2005.13541

Natural axion model from flavour

Salvador Centelles Chuliá·Christian Döring·Werner Rodejohann·Ulises J. Saldaña-Salazar
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Abstract

We explore a common symmetrical origin for two long standing problems in particle physics: the strong CP and the fermion mass hierarchy problems. The Peccei--Quinn mechanism solves the former one with an anomalous global $U(1)_{\rm PQ}$ symmetry. Here we investigate how this $U(1)_{\rm PQ}$ could at the same time explain the fermion mass hierarchy. We work in the context of a four-Higgs-doublet model which explains all quark and charged fermion masses with natural, i.e.\ order $1$, Yukawa couplings. Moreover, the axion of the model constitutes a viable dark matter candidate and neutrino masses are incorporated via the standard type-I seesaw mechanism. A simple extension of the model allows for Dirac neutrinos.

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Salvador Centelles Chuliá, Christian Döring, Werner Rodejohann, Ulises J. Saldaña-Salazar. 2020-05-27. Natural axion model from flavour. https://arxiv.org/abs/2005.13541

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