Constraining dynamical dark energy with a divergence-free parametrization in the presence of spatial curvature and massive neutrinos

In this Letter, we report the results of constraining the dynamical dark energy with a divergence-free parameterization, w(z)=w0+wa(ln(2+z)1+z−ln2), in the presence of spatial curvature and massive neutrinos, with the 7-yr WMAP temperature and polarization data, the power spectrum of LRGs derived from SDSS DR7, the Type Ia supernova data from Union2 sample, and the new measurements of H0 from HST, by using a MCMC global fit method. Our focus is on the determinations of the spatial curvature, Ωk, and the total mass of neutrinos, ∑mν, in such a dynamical dark energy scenario, and the influence of these factors to the constraints on the dark energy parameters, w0 and wa. We show that Ωk and ∑mν can be well constrained in this model; the 95% CL limits are: −0.0153<Ωk<0.0167 and ∑mν<0.56eV. Comparing to the case in a flat universe, we find that the error in w0 is amplified by 25.51%, and the error in wa is amplified by 0.14%; comparing to the case with a zero neutrino mass, we find that the error in w0 is amplified by 12.24%, and the error in wa is amplified by 1.63%.