Degenerate neutrinos from a supersymmetric A_4 model

M. Hirsch; J. C. Romao; S. Skadhauge; J. W. F. Valle; A. Villanova del Moral

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arXiv · hep-ph/0312244

Degenerate neutrinos from a supersymmetric A_4 model

M. Hirsch·J. C. Romao·S. Skadhauge·J. W. F. Valle·A. Villanova del Moral

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Abstract

We investigate the supersymmetric A_4 model recently proposed by Babu, Ma and Valle. The model naturally gives quasi-degenerate neutrinos that are bi-largely mixed, in agreement with observations. Furthermore, the mixings in the quark sector are constrained to be small, making it a complete model of the flavor structure. Moreover, it has the interesting property that CP-violation in the leptonic sector is maximal (unless vanishing). The model exhibit a close relation between the slepton and lepton sectors and we derive the slepton spectra that are compatible with neutrino data and the present bounds on flavor-violating charged lepton decays. The prediction for the branching ratio of the decay tau -> mu gamma has a lower limit of 10^{-9}. In addition, the overall neutrino mass scale is constrained to be larger than 0.3 eV. Thus, the model will be tested in the very near future.

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M. Hirsch, J. C. Romao, S. Skadhauge, J. W. F. Valle, A. Villanova del Moral. 2003-12-17. Degenerate neutrinos from a supersymmetric A_4 model. https://arxiv.org/abs/hep-ph/0312244

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