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arXiv · 1502.03105

Invariant approach to CP in family symmetry models

Gustavo C. Branco·Ivo de Medeiros Varzielas·Steve F. King
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Abstract

We propose the use of basis invariants, valid for any choice of CP transformation, as a powerful approach to studying specific models of CP violation in the presence of discrete family symmetries. We illustrate the virtues of this approach for examples based on $A_4$ and $\Delta(27)$ family symmetries. For $A_4$, we show how to elegantly obtain several known results in the literature. In $\Delta(27)$ we use the invariant approach to identify how explicit (rather than spontaneous) CP violation arises, which is geometrical in nature, i.e. persisting for arbitrary couplings in the Lagrangian.

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Gustavo C. Branco, Ivo de Medeiros Varzielas, Steve F. King. 2015-02-10. Invariant approach to CP in family symmetry models. https://doi.org/10.1103/physrevd.92.036007

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