Asymmetric Self-interacting Dark Matter and Neutrino Mass via Dirac Leptogenesis

We propose a framework to address the observed baryon asymmetry considering neutrinos as Dirac particles and dark matter to be self-interacting. The Standard Model is extended by U (1) B−L × U (1) D symmetry. In addition to the three right-handed neutrinos, the Standard Model particle content is extended by two more fermion fields; one of them is a S U (2) singlet and the other one is S U (2) doublet, both charged under the extended symmetry. A Z 2 symmetry is imposed under which the doublet is positive while the singlet is negative. The singlet, being the lightest dark sector particle, acts as the dark matter. The U (1) D symmetry of the dark sector is spontaneously broken and the corresponding gauge boson Z ′ not only mediates the self-interaction among dark matter particles, but also facilitates the annihilation of the symmetric component of dark matter. CP-violating out of equilibrium decay of another heavy Z 2 odd S U (2) scalar doublet N into leptonic and dark sectors produce the observed baryon asymmetry and dark matter density. Moreover, Z ′ also mixes with the standard model Z -boson opening up a portal for the direct detection of dark matter.