A 331 WIMPy Dark Radiation Model
  Recent observations suggest that the number of relativistic degrees of
freedom in the early universe might exceed what is predicted in the standard
cosmological model. If even a small, percent-level fraction of dark matter
particles are produced relativistically, they could mimic the effect of an
extra realistic species at matter-radiation equality while obeying BBN, CMB and
Structure Formation bounds. We show that this scenario is quite naturally
realized with a weak-scale dark matter particle and a high-scale ``mother''
particle within a well motivated 3-3-1 gauge model, which is particularly
interesting for being consistent with electroweak precision measurements, with
recent LHC results, and for offering a convincing explanation for the number of
generations in the Standard Model.
