Constraints on massive sterile plus active neutrino species in non
  minimal cosmologies
  Cosmological measurements are affected by the energy density of both active
and sterile massive neutrinos. We extend here a recent analysis of current
cosmological data to non minimal cosmologies. Several possible scenarios are
examined: a constant w \neq -1 dark energy equation of state, a non flat
universe, a time varying dark energy component and coupled dark matter dark
energy universes or modified gravity scenarios. When considering cosmological
data only, (3+2) massive neutrino models with ~0.5 eV sterile species are
allowed at 95% CL. This scenario has been shown to reconcile reactor, LSND and
MiniBooNE positive signals with null results from other searches. Big Bang
Nucleosynthesis bounds could compromise the viability of (3+2) models if the
two sterile species are fully thermalized states at decoupling.
