Radiatively Generated Leptogenesis in S4 Flavor Symmetry Models

Abstract EN

We study how leptogenesis can be implemented in the seesaw models with S4 flavor symmetry, which lead to the tri-bimaximal neutrino mixing matrix.

By considering renormalization group evolution from a high-energy scale of flavor symmetry breaking (the GUT scale is assumed) to the low-energy scale of relevant phenomena, the off-diagonal terms in a combination of Dirac Yukawa-coupling matrix can be generated and the degeneracy of heavy right-handed neutrino Majorana masses can be lifted.

As a result, the flavored leptogenesis is successfully realized.

We also investigate how the effective light neutrino mass |〈mee〉| associated with neutrinoless double beta decay can be predicted along with the neutrino mass hierarchies by imposing the experimental data on the low-energy observables.

We find a link between the leptogenesis and the neutrinoless double beta decay characterized by |〈mee〉| through a high-energy CP phase ϕ, which is correlated with the low-energy Majorana CP phases.

It is shown that the predictions of |〈mee〉| for some fixed parameters of the high-energy physics can be constrained by the current observation of baryon asymmetry.