New cosmological constraints with extended-Baryon Oscillation Spectroscopic Survey DR14 quasar sample

Abstract

We update the constraints on the cosmological parameters by adopting the Planck data released in 2015 and baryon acoustic oscillation (BAO) measurements including the new DR14 quasar sample measurement at redshift z= 1.52 , and we conclude that the six-parameter Λ CDM model is preferred. Exploring some extensions to the Λ CDM model, we find that the equation of state of dark energy reads w= - 1.036 ± 0.056 in the wCDM model, the effective number of relativistic degrees of freedom in the Universe is Neff=3.09-0.20+0.18 in the Neff+ Λ CDM model and the spatial curvature parameter is Ω k= (1.8 ± 1.9) × 10 - 3 in the Ω k+ Λ CDM model at 68 % confidence level (C.L.), and the 95 % C.L. upper bounds on the sum of three active neutrinos masses are ∑ mν< 0.16 eV for the normal hierarchy (NH) and ∑ mν< 0.19 eV for the inverted hierarchy (IH) with Δχ2≡χNH2-χIH2=-1.25.