An improved limit on the neutrino mass with CMB and redshift-dependent halo bias-mass relations

We use measurements of luminosity-dependent galaxy bias at several different redshifts, SDSS at z=0.05, DEEP2 at Z=1 and LBGs at z=3.8, combined with WMAP five-year cosmic microwave background anisotropy data and SDSS Red Luminous Galaxy survey three-dimensional clustering power spectrum to put constraints on cosmological parameters. Fitting this combined dataset, we show that the luminosity-dependent bias data that probe the relation between halo bias and halo mass and its redshift evolution are very sensitive to sum of neutrino masses: in particular we obtain the upper limit Σmν<0.28eV at the 95% confidence level for a ΛCDM + mν model, with a σ8 equal to σ8=0.759∓ 0.025 (1 σ). When we allow the dark energy equation of state model with the 95% confidence level upper limit on the neutrino masses at Σmν < 0.59eV. The constraint on the dark energy equation of state further improves to w= -1.125∓0.092 when using also ACBAR and supernovae Union data, in addition to above, with a prior on the Hubble constant from the Hubble Space Telescope.