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arXiv · 1107.3486

Discrete Flavour Symmetries in Light of T2K

Reinier de Adelhart Toorop·Ferruccio Feruglio·Claudia Hagedorn
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Abstract

We show that a non-vanishing angle theta_13 of order 0.1 can be predicted in the framework of discrete flavour symmetries. We assume that left-handed leptons transform as triplets under a group G_f which is broken in such a way that neutrino and charged lepton sectors remain invariant under the subgroups G_nu and G_e of G_f, respectively. In this limit mixing angles and the Dirac CP violating phase delta_CP are determined. By choosing G_f=Delta(6 n^2) (n=4,8), G_nu=Z_2 x Z_2 and G_e=Z_3 we find sin^2 theta_13=0.045(0.011) for n=4(8). At the same time theta_23 and theta_12 remain close to their experimental best fit values, particularly in the case n=8, where sin^2 theta_23 = 0.424 and sin^2 theta_12 = 0.337. delta_CP is predicted to be 0 or pi so that CP is conserved in our examples.

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Reinier de Adelhart Toorop, Ferruccio Feruglio, Claudia Hagedorn. 2011-07-18. Discrete Flavour Symmetries in Light of T2K. https://doi.org/10.1016/j.physletb.2011.08.013

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