The origin of flavour is one of the big puzzles in particle physics. The observed baryon asymmetry of the Universe (BAU) also supports the need for a more fundamental theory. We adopt the approach to
the problem of flavour based on discrete flavour symmetries, and accommodating baryogenesis via leptogenesis.

In the SU(5)xA5 Golden Ratio flavour model, with the introduction of only one NLO operator we can simultaneously accommodate the observed neutrino masses, mixing angles and baryon asymmetry successfully even at a $1\sigma$ level. Then we improve the calculation by solving the Boltzmann equations of the system. The phenomenological predictions only change a little with respect to those get by using the analytic approximation. Among the many predictions of the model we find, for instance, that the neutrinoless double beta decay effective Majorana mass $m_{ee}$ lies between 3.3~meV and 14.3~meV.

                                                           Host: Prof. Xiao-Gang He