Abstract

We propose a model based on the SU(5) grand unification with an extra A(4) circle times Z(2) circle times Z(2)' circle times Z(2)'' circle times U(1)(f) flavor symmetry, which accounts for the pattern of the SM fermion masses and mixings. The observed hierarchy of charged fermion masses and quark mixing matrix elements arises from a generalized Froggatt-Nielsen mechanism triggered by a scalar 24 representation of SU(5) charged under the global U(1)(f) and acquiring a VEV at the GUT scale. The light neutrino masses are generated via a radiative seesaw mechanism with a single heavy Majorana neutrino and neutral scalars running in the loops. The model predictions for both quark and lepton sectors are in good agreement with the experimental data. The model predicts an effective Majorana neutrino mass, relevant for neutrinoless double beta decay, with values m(beta beta) = 4 and 50 meV for the normal and the inverted neutrino spectrum, respectively. The model also features a suppression of CP violation in neutrino oscillations, a low scale for the heavy Majorana neutrino (few TeV) and, due to the unbroken Z(2) symmetry, a natural dark matter candidate.