Asymmetric Dark Matter From Triplet Scalar Leptogenesis

In this article we extend the standard model with a SU(2) singlet leptonic Dirac fermion χ, which represents the candidate of dark matter, and a triplet scalar ∆. In the early Universe, the CP violating out of equilibrium decay of ∆ generates a net B − L asymmetry in the SM sector, where B and L represents the total baryon and lepton number respectively. A part of this asymmetry gets transferred to the dark sector through a higher dimensional operator which conserve B − L, while the B + L violating sphalerons keeps converting B − L asymmetry to the observed B asymmetry. In addition, we introduce a singlet scalar field φ which mixes with the SM-Higgs to give a resonance channel to annihilate the symmetric component of DM and also gives direct detection signal. In our model, the active neutrinos get small masses by the induced vacuum expectation value (vev) of the triplet scalar ∆. In the later part of the paper we discuss all the constraints coming from invisible Higgs decay, Higgs signal strength, DM direct detection and relic density of DM