English

Constraints on a non-gaussian ($\chi_m^2$) CDM model

Astrophysics 2009-10-31 v2

Abstract

We consider constraints on the structure formation model based on non-Gaussian fluctuations generated during inflation, which have χm2\chi_m^2 distributions. Using three data sets, the abundance of the clusters at z=0z=0, moderate zz and the correlation length, we show that constraints on the non-Gaussianity and the amplitude of fluctuations and the density parameter can be obtained. We obtain an upper bound for Ωm\Omega_m and a lower bound for the non-Gaussianity and the amplitude of the fluctuations. Using the abundance of clusters at z0.6z \sim 0.6, for the spectrum parameterized by cold dark matter (CDM) shape parameter Γ=0.23\Gamma=0.23, we obtain an upper bound for the density parameter Ωm0.5\Omega_m \sim 0.5 and lower bounds for the amplitude σ80.7\sigma_8 \sim 0.7 and for the non-Gaussianity of fluctuations G2G \sim 2 (m200)(m \sim 200), where G=1 for Gaussian.

Keywords

Cite

@article{arxiv.astro-ph/9903027,
  title  = {Constraints on a non-gaussian ($\chi_m^2$) CDM model},
  author = {Kazuya Koyama and Jiro Soda and Atsushi Taruya},
  journal= {arXiv preprint arXiv:astro-ph/9903027},
  year   = {2009}
}

Comments

7 pages, 3 figures, MNRAS in press

R2 v1 2026-07-22T09:46:39.296Z