  Non-relativistic dark matter scattering with nucleons is constrained by
direct detection experiments. We use the XENON constraints on the
spin-independent and spin-dependent cross section for dark matter scattering
with nucleons to constrain a hypothetical Majorana fermionic dark matter
particle's couplings to the Higgs boson and Z boson. In the procedure we
illustrate the change in the dark matter nucleon cross section as one goes from
non-relativistic, coherent scattering to relativistic, incoherent scattering.
While the Z invisible decay width excludes directly couplings of dark matter to
ordinary matter, by introducing a light Z' portal to the dark sector, a
relatively large dark matter nucleon cross section can be preserved even with
accelerator experiment constraints for dark matter with a mass of ~10 GeV

High Energy Physics - Phenomenology