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arXiv · 1510.02501

Neutrino Mixing: $A_4$ Variations

Ernest Ma
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Abstract

In the context of the non-Abelian discrete symmetry $A_4$, the neutrino mass matrix has been studied extensively. A brief update is presented to focus on the conceptual shift from tribimaximal mixing ($θ_{13} = 0$, $θ_{23} = π/4$, $\tan^2 θ_{12} = 1/2$) to $\underline{\rm cobimaximal}$ mixing ($θ_{13} \neq 0$, $θ_{23} = π/4$, $δ_{CP} = \pm π/2$) which agrees well with present data. Three specific realistic examples are proposed, two with three and the third with just two parameters.

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Ernest Ma. 2015-11-12. Neutrino Mixing: $A_4$ Variations. https://doi.org/10.1016/j.physletb.2015.11.049

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