中文

Cosmological parameters from large scale structure observations

天体物理学 2007-05-23 v3

摘要

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\alpha clouds and CMB temperature fluctuations is analyzed. Using a χ2\chi^2 minimization method, assuming ΩΛ+Ωmatter=1\Omega_{\Lambda}+\Omega_{\rm{matter}} =1 and no contribution from gravity waves, we found that a tilted Λ\LambdaMDM model with one sort of massive neutrinos and the parameters n=1.12±0.10n=1.12\pm 0.10, Ωm=0.41±0.11\Omega_m=0.41\pm 0.11 (ΩΛ=0.59±0.11\Omega_{\Lambda}=0.59\pm0.11), Ωcdm=0.31±0.15\Omega_{cdm}=0.31\pm 0.15, Ων=0.059±0.028\Omega_{\nu}=0.059\pm 0.028, Ωb=0.039±0.014\Omega_b=0.039\pm 0.014 and h=0.70±0.12h=0.70\pm 0.12 matches observational data best. The 1σ\sigma (68.3%) confidence limits on each cosmological parameter, which are obtained by marginalizing over the other parameters, are 0.82n1.390.82\le n\le1.39, 0.19Ωm10.19\le\Omega_m\le 1 (0ΩΛ0.810\le\Omega_{\Lambda}\le 0.81), 0Ων0.170\le\Omega_{\nu}\le 0.17, 0.021Ωb0.130.021\le \Omega_b\le 0.13 and 0.38h0.850.38\le h\le 0.85 1.5bcl3.51.5\le b_{cl}\le 3.5. Here bclb_{cl} is the cluster bias parameter. The best-fit parameters for 31 models which are inside of 1σ1\sigma range of the best model are presented. It is shown also that observational data set used here rules out the class of CDM models with h0.5h\ge 0.5, scale invariant primordial power spectrum, zero cosmological constant and spatial curvature at very high confidence level, >99.99>99.99%. The corresponding class of MDM models are ruled out at 95\sim 95% C.L.

关键词

引用

@article{arxiv.astro-ph/9912511,
  title  = {Cosmological parameters from large scale structure observations},
  author = {B. Novosyadlyj and R. Durrer and S. Gottloeber and V. N. Lukash and S. Apunevych},
  journal= {arXiv preprint arXiv:astro-ph/9912511},
  year   = {2007}
}

备注

19 pages, 9 figures. Accepted for publication in A&A