2000/02/29 by B. Novosyadlyj, R. Durrer, S. Gottloeber +2
Physics and Astronomy · #astro-ph
published as Grav.Cosmol.Suppl. 6 (2000) 107-115 · 9 pages, 1 figures (Proceedings of IV International Conference "Cosmology. Relativistic Astrophysics. Cosmoparticle Physics", Moscow, 17-24 October 1999; to be published in "Gravitation & Cosmology, Vol. 5 (1999), Supplement)
arxiv created 2000/02/29 · arxiv updated 2009/12/01
The possibility of determining cosmological parameters on the basis of a wide set of observational data including the Abell-ACO cluster power spectrum and mass function, peculiar velocities of galaxies, the distribution of Ly-α clouds and CMB temperature fluctuations is analyzed. Using a χ2 minimization method, assuming ΩΛ+Ωm =1 and no contribution from gravity waves, we found that a tilted ΛMDM model with one sort of massive neutrinos and the parameters n≈ 1.12, Ωm≈ 0.4 (ΩΛ≈ 0.6), Ωcdm≈ 0.3, Ων≈ 0.06, Ωb≈ 0.04 and h≈ 0.7 matches observational data best. Ων is higher for more species of massive neutrinos, ∼ 0.1 for two and ∼ 0.13 for three species. Ωm raises by ∼ 0.08 and ∼ 0.15 respectively. Varying only a subset of parameters and fixing the others shows also that the observational data set used here rules out pure CDM models with h≥ 0.5, scale invariant primordial power spectrum, zero cosmological constant and spatial curvature at a very high confidence level, >99.99%. The corresponding class of MDM models are ruled out at ∼ 95% C.L. It is notable also that this data set determines the amplitude of scalar fluctuations approximately at the same level as COBE four-year data. It indicates that a possible tensor component in the COBE data cannot be very substantial.