New upper limit on the total neutrino mass from the 2 degree field galaxy redshift survey

We constrain fν≡Ων/Ωm, the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find fν<0.13 (at 95% confidence) for a prior of 0.1<Ωm<0.5, and assuming the scalar spectral index n=1. This translates to an upper limit on the total neutrino mass mν,tot<1.8   eV for “concordance” values of Ωm and the Hubble constant.