Right-handed neutrino dark matter in $U(1)_X$SSM

There is strong evidence for the existence of dark matter in a number of current experiments. We study dark matter using the $U(1)_X$SSM obtained from the $U(1)_X$ extension of the minimal supersymmetric standard model (MSSM). In the $U(1)_X$SSM, we use the right-handed neutrino as a dark matter candidate, whose lightest mass eigenstate has cold dark matter features. In this paper, the relic density of right-handed neutrino as dark matter is investigated. For dark matter scattering, both spin-independent and spin-dependent cross sections are studied. In the final numerical results obtained, some parameter spaces can satisfy the constraints of the relic density and dark matter direct detection experiments.