Understanding the differences in neutrino and charged-fermion flavour structures

by Oscar Vives (CERN-PH/TH)

Friday 17 Jun 2005, 14:00 → 15:00 Europe/Zurich

TH Auditorium (CERN)

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 any particular flavour symmetry, 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 θ₁₃ comes entirely from the charged lepton sector and, using the difference of the solar angle from maximality, we can fix the mass of the lightest neutrino.