Symmetry origin of Baryon Asymmetry, Dark Matter and Neutrino Mass

Abstract: We propose a minimal model based on lepton number symmetry (and violation), to address a common origin of baryon asymmetry, dark matter and neutrino mass generation. The model consists of a vector like fermion to constitute the dark sector, three right handed neutrinos (RHN) to dictate leptogenesis and neutrino mass, while an additional complex scalar is assumed to be present in the early universe the decay of which produces both DM and RHN via lepton number violating and lepton number conserving interactions respectively. Interestingly, the presence of the same scalar helps in making the electroweak vacuum stable till the Planck scale. The unnatural largeness and smallness of the parameters required to describe correct experimental limits are attributed to lepton number violation. The allowed parameter space of the model is illustrated via a numerical scan.