Cosmological measurements are affected by the energy density of massive neutrinos. We extend here a recent analysis of current cosmological data to nonminimal cosmologies. Several possible scenarios are examined: a constant $w\ne -1$ dark energy equation of state, a nonflat 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 $\sim 0.5\mathrm{eV}$ sterile species are allowed at 95% confidence level. 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.

• Received 28 December 2011

DOI:https://doi.org/10.1103/PhysRevD.85.083522