New constraints on neutrino masses from cosmology

By combining data from cosmic microwave background (CMB) experiments (including the recent WMAP third year results), large scale structure (LSS) and Lyman-alpha forest observations, we derive upper limits on the sum of neutrino masses of Sigma m(v) 1 eV or < 0.05 eV the cosmological energy density in sterile neutrinos is always constrained to be omega(nu) < 0.003 at 95% c.l. However, for a sterile neutrino mass of similar to 0.25 eV, omega(nu) can be as large as 0.01. (c) 2006 Elsevier B.V. All rights reserved