Direct detection of fermion dark matter in the radiative seesaw model

We consider the scenario in the radiative seesaw model where the dark matter particle is the lightest Z(2)-odd fermion. We identify the regions of the parameter space of the model compatible with neutrino oscillation data, with the upper limits from rare charged-lepton decays and with the observed dark matter abundance via thermal freeze-out, and we compute the dark matter scattering cross section with nuclei via the one-loop exchange of a photon, a Z(0)-boson or a Higgs boson. We find that the predicted spin-independent cross section lies below the current LUX limit, although, for some choices of parameters, above the expected sensitivity of XENON1T or LZ.