Neutrino Masses and Sterile Neutrino Dark Matter from the PeV Scale
  We show that active neutrino masses and a keV-GeV mass sterile neutrino dark
matter candidate can result from a modified, low energy seesaw mechanism if
right-handed neutrinos are charged under a new symmetry broken by a scalar
field vacuum expectation value at the PeV scale. The dark matter relic
abundance can be obtained through active-sterile oscillation, freeze-in through
the decay of the heavy scalar, or freeze-in via non-renormalizable interactions
at high temperatures. The low energy effective theory maps onto the widely
studied nuMSM framework.
