Revisiting the scotogenic model with scalar dark matter

Abstract: The scotogenic model is a well motivated scenario that provides both an explanation for neutrino masses and for dark matter. We focus on a real scalar dark matter candidate in this model, produced through standard thermal freeze-out. We analyze the parameter space of the model compatible with the observed dark matter relic abundance, direct and indirect detection searches, limits from lepton flavour violating decays and constraints from the neutrino sector. As the mass differences of the dark matter with the neutral and charged states are found to be small, the new scalars and fermions of the theory will have macroscopic lifetimes, and could thus be potentially detected with long-lived particle signatures at colliders. We find regions in the parameter space to be - partially or fully - consistent with the dark matter relic abundance, and the prediction of a long-lived charged scalar or lightest neutral fermion in the scotogenic scenario, for dark matter masses below 500 GeV. We discuss on the collider phenomenology in some detail.