Understanding the differences in neutrino and charged-fermion flavour structures

Oscar Vives

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arXiv · hep-ph/0504079

Understanding the differences in neutrino and charged-fermion flavour structures

Oscar Vives

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Abstract

We present a new mechanism to explain naturally and through a common flavour symmetry the mildly hierarchical neutrino masses with large mixings and the hierarchical Yukawa matrices with small mixing angles. Although this mechanism is not linked to a particular flavour symmertry, it is particularly simple in the framework of a SU(3) flavour symmetry. In this model, we obtain exactly maximal atmospheric mixing, large although not maximal solar mixing and a normal neutrino hierarchy. All neutrino parameters are basically fixed. For instance, we predict that the angle $θ_{13}$ comes entirely from the charged lepton sector and, using the difference of the solar angle from maximality, we can fix the mass of lightest neutrino.

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Oscar Vives. 2005-05-20. Understanding the differences in neutrino and charged-fermion flavour structures. https://arxiv.org/abs/hep-ph/0504079

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