Neutrino mass, leptogenesis and sterile neutrino dark matter in inverse seesaw framework

We study S-4 flavor symmetric inverse seesaw model which has the possibility of simultaneously addressing neutrino phenomenology, dark matter (DM) and baryon asymmetry of the universe (BAU) through leptogenesis. The model is the extension of the standard model by the addition of two (RH) neutrinos and three sterile fermions leading to a keV scale sterile neutrino DM and two pairs of quasi-Dirac states. The CP violating decay of the lightest quasi-Dirac pair present in the model generates lepton asymmetry which then converts to BAU. Thus, this model can provide a simultaneous solution for nonzero neutrino mass, DM content of the universes and the observed baryon asymmetry. The S4 flavor symmetry in this model is augmented by additional Z(4) x Z(3) symmetry to constrain the Yukawa Lagrangian. A detailed numerical analysis has been carried out to obtain DM mass, DM-active mixing as well as BAU both for normal hierarchy as well as inverted hierarchy. We try to correlate the two cosmological observables and found a common parameter space satisfying the DM phenomenology and BAU. The parameter space of the model is further constrained from the latest cosmological bounds on the observables.

Automated summary

The study focuses on the S-4 flavor symmetric inverse seesaw model as a potential solution for addressing neutrino phenomenology, dark matter, and baryon asymmetry through leptogenesis. The model introduces additional neutrinos and sterile fermions to the standard model, leading to a keV scale sterile neutrino dark matter and quasi-Dirac states. The CP violating decay in the model generates lepton asymmetry which then converts to baryon asymmetry, providing a simultaneous solution for these cosmological phenomena.