Neutrino specific spin-3/2 dark matter

In this paper we consider a spin-32 dark matter (DM) particle which couples to neutrinos, as a viable candidate to produce the observed DM relic density through the thermal freeze-out mechanism. The couplings of DM to neutrinos is considered first in a general dimension-6 effective field theory framework. We then consider two specific neutrino-portal models discussed in the literature. In the first model DM couples to the standard model neutrinos through mixing generated by a sterile pseudo-Dirac massive neutrino, and in the second model we consider the U(1)Lμ-Lτ gauge symmetric model. For each of these models we explore the parameter space required to generate the observed relic density. The constraints on the parameters of these models from the existing and proposed neutrino experiments, as well as from existing cosmological and astrophysical bounds, are considered in the context of the relic density calculations.