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arXiv · 1407.5826

Nonzero $θ_{13}$ and Leptogenesis in a Type-I See-saw Model with $A_4$ Symmetry

Abstract

In the light of recent discovery of nonzero $θ_{13}$, we have analyzed the Altarelli-Feruglio $A_4$ flavor symmetry model extended with additional flavon. The inclusion of the new field leads to the deviation from exact tri-bimaximal neutrino mixing pattern in the context of type-I see-saw by producing a nonzero $θ_{13}$ consistent with the recent experimental results at the leading order. A sum rule for light neutrino masses is also obtained in this context. The set-up constraints the two Majorana phases involved in the lepton mixing matrix in terms of $A_4$ parameter space. We have shown that a nonzero lepton asymmetry can be generated while next-to-leading order contributions to the neutrino Yukawa couplings are considered. The two Majorana phases play crucial role in CP-asymmetry parameter and the involvement of $θ_{13}$ in it, is exercised.

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BibTeXRIS

Biswajit Karmakar, Arunansu Sil. 2015-02-12. Nonzero $θ_{13}$ and Leptogenesis in a Type-I See-saw Model with $A_4$ Symmetry. https://doi.org/10.1103/physrevd.91.013004

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