Right-handed neutrino dark matter in a U(1) extension of the Standard Model

Abstract

We consider minimal U(1) extensions of the Standard Model in which one of the right-handed neutrinos is charged under the new gauge symmetry and plays the role of dark matter. In particular, we perform a detailed phenomenological study for the case of a U(1)(B-L)3 flavoured B-L symmetry. If perturbativity is required up to high-scales, we find an upper bound on the dark matter mass of mχ2 TeV, significantly stronger than that obtained in simplified models. Furthermore, if the U(1)(B-L) 3 breaking scalar has significant mixing with the SM Higgs, there are already strong constraints from direct detection. On the other hand, there remains significant viable parameter space in the case of small..