English

Abundance and evolution of galaxy clusters in cosmological models with massive neutrino

Astrophysics 2009-11-07 v3

Abstract

The time evolution of the number density of galaxy clusters and their mass and temperature functions are used to constrain cosmological parameters in the spatially flat dark matter models containing a fraction of hot particles (massive neutrino) additional to cold and baryonic matter. We test the modified MDM models with cosmic gravitational waves and show that they neither pass the cluster evolution test nor reproduce the observed height of the first acoustic peak in ΔT/T\Delta T/T spectrum, and therefore should be ruled out. The models with a non-zero cosmological constant are in better agreement with observations. We estimate the free cosmological parameters in Λ\LambdaMDM with a negligible abundance of gravitational waves, and find that within the parameter ranges h(0.6,0.7)h\in (0.6, 0.7), n(0.9,1.1)n\in (0.9, 1.1), (i) the value of ΩΛ\Omega_\Lambda is strongly affected by a small fraction of hot dark matter, fνΩν/Ωm(0,0.2)f_\nu\equiv\Omega_\nu /\Omega_m\in (0, 0.2): 0.45<ΩΛ<0.70.45 <\Omega_\Lambda <0.7 (1σ1\sigma CL), and (ii) the redshift evolution of galaxy clusters alone reveals the following explicit correlation between ΩΛ\Omega_\Lambda and fνf_\nu: ΩΛ+0.5fν=0.65±0.1\Omega_\Lambda +0.5f_\nu =0.65\pm 0.1. The present accuracy of observational data allows only to bound the fraction of hot matter, fν(0,0.2)f_\nu\in (0, 0.2) (the number of massive neutrino species remains undelimited, Nν=1,2,3N_\nu =1, 2, 3).

Keywords

Cite

@article{arxiv.astro-ph/0110426,
  title  = {Abundance and evolution of galaxy clusters in cosmological models with massive neutrino},
  author = {N. A. Arhipova and T. Kahniashvili and V. N. Lukash},
  journal= {arXiv preprint arXiv:astro-ph/0110426},
  year   = {2009}
}

Comments

9 pages, 7 figures, submitted in A&A