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arXiv · 1601.00138

Soft $A_4 \to Z_3$ Symmetry Breaking and Cobimaximal Neutrino Mixing

Ernest Ma
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Abstract

I propose a model of radiative charged-lepton and neutrino masses with $A_4$ symmetry. The soft breaking of $A_4$ to $Z_3$ lepton triality is accomplished by dimension-three terms. The breaking of $Z_3$ by dimension-two terms allow cobimaximal neutrino mixing $(θ_{13} \neq 0, θ_{23} = π/4, δ_{CP} = \pm π/2)$ to be realized with only very small finite calculable deviations from the residual lepton triality. This construction solves a long-standing technical problem inherent in renormalizable $A_4$ models since their inception.

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Ernest Ma. 2016-01-02. Soft $A_4 \to Z_3$ Symmetry Breaking and Cobimaximal Neutrino Mixing. https://doi.org/10.1016/j.physletb.2016.02.032

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