Asymmetric mediator in scotogenic model

Abstract

The scotogenic model is the Standard Model (SM) with Z2 symmetry and the addition of Z2 odd right-handed Majorana neutrinos and SU(2)L doublet scalar fields. We have extended the original scotogenic model by an additional Z2 odd singlet scalar field that plays a role in dark matter. In our model, the asymmetries of the lepton and Z2 odd doublet scalar are simultaneously produced through CP-violating right-handed neutrino decays. While the former is converted into baryon asymmetry through the sphaleron process, the latter is relaid to the DM density through the decay of SU(2)L doublet scalar that is named “asymmetric mediator”. In this way, we provide an extended scotogenic model that predicts the energy densities of baryon and dark matter being in the same order of magnitude, and also explains the low-energy neutrino masses and mixing angles.