Scalar dark matter, neutrino mass and leptogenesis in a U(1)B-Lmodel

Abstract

We investigate the phenomenology of singlet scalar dark matter (DM) in a simple U(1) B-L gauge extension of the standard model, made anomaly-free with four exotic fermions. The enriched scalar sector and the new gauge boson Z′, associated with U(1) gauge extension, connect the dark sector to the visible sector. We compute relic density, consistent with Planck limit and a Z′ mediated DM-nucleon cross section, compatible with PandaX bound. The mass of Z′ and the corresponding gauge coupling are constrained from LEP-II and LHC dilepton searches. We also briefly scrutinize the tree-level neutrino mass with a dimension five operator. Furthermore, resonant leptogenesis phenomena is discussed with TeV-scale exotic fermions to produce the observed baryon asymmetry of the Universe. Further, we briefly explain the impact of flavor in leptogenesis and we also project the combined constraints on Yukawa, consistent with oscillation data and observed baryon asymmetry. Additionally, we restrict the new gauge parameters by using the existing data on branching ratios of rare B(τ) decay modes. We see that the constraints from the dark sector are much more stringent from the flavor sector. © 2021 IOP Publishing Ltd.