CONSTRAINTS ON NON-FLAT COSMOLOGIES WITH MASSIVE NEUTRINOS AFTER PLANCK 2015

Abstract

We investigate two dark energy cosmological models (i.e., the Lambda CDM and phi CDM models) with massive neutrinos assuming two different neutrino mass hierarchies in both the spatially flat and non-flat scenarios, where in the phi CDM model the scalar field possesses an inverse power-law potential, V(phi) proportional to phi(-alpha) (alpha > 0). Cosmic microwave background data from Planck. 2015, baryon acoustic oscillation data from 6dFGS, SDSS-MGS, BOSS-LOWZ and BOSS CMASS-DR11, the joint light-curve analysis compilation of SNe Ia apparent magnitude observations, and the Hubble Space Telescope H-0 prior, are jointly employed to constrain the model parameters. We first determine constraints assuming three species of degenerate massive neutrinos. In the spatially flat (non-flat) Lambda CDM model, the sum of neutrino masses is bounded as Sigma m(nu) < 0.165(0.299) eV at 95% confidence level (CL). Correspondingly, in the flat (non-flat) phi CDM model, we find Sigma m(nu) < 0.164(0.301) eV at 95% CL. The inclusion of spatial curvature as a free parameter results in a significant broadening of confidence regions for Sigma m(nu) igenstate, we obtain similar conclusions to those obtained in the degenerate neutrino mass scenario. In addition, the results show that the bounds on Sigma m(nu) based on two different neutrino mass hierarchies have insignificant differences in the spatially flat case for both the Lambda CDM and phi CDM models; however, the corresponding differences are larger in the nonflat case.