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arXiv · 2307.14410

Quarks at the modular $S_4$ cusp

I. de Medeiros Varzielas·M. Levy·J. T. Penedo·S. T. Petcov
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Abstract

We analyse the possibility of describing quark masses, mixing and CP violation in $S'_4$ modular flavour models without flavons. We focus on the case where the closeness of the modulus to the point of residual $\mathbb{Z}^{ST}_3$ symmetry (the cusp) plays a role in generating quark mass hierarchies and discuss the role modular form normalisations play in such constructions. We find that fitting quark data requires explicit CP breaking, unless a second modulus is introduced.

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I. de Medeiros Varzielas, M. Levy, J. T. Penedo, S. T. Petcov. 2023-07-26. Quarks at the modular $S_4$ cusp. https://arxiv.org/abs/2307.14410

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