{
  "id": "astro-ph/0107442",
  "version": "v2",
  "published": "2001-07-23T18:24:00.000Z",
  "updated": "2001-12-21T15:15:38.000Z",
  "title": "The Central Mass and Phase-Space Densities of Dark Matter Halos: Cosmological Implications",
  "authors": [
    "Paul R. Shapiro",
    "Ilian T. Iliev"
  ],
  "comment": "12 pages, 3 figures, ApJ Letters, in press (2002); Changed to match the accepted version. Results and figures unchanged; text revisions only",
  "doi": "10.1086/339243",
  "categories": [
    "astro-ph"
  ],
  "abstract": "Current data suggest that the central mass densities $\\rho_0$ and phase-space densities $Q\\equiv\\rho_0/\\sigma_V^3$ of cosmological halos in the present universe are correlated with their velocity dispersions $\\sigma_V$ over a very wide range of $\\sigma_V$ from less than 10 to more than 1000 $\\rm km s^{-1}$. Such correlations are an expected consequence of the statistical correlation of the formation epochs of virialized objects in the CDM model with their masses; the smaller-mass halos typically form first and merge to form larger-mass halos later. We have derived the $Q-\\sigma_V$ and $\\rho_0-\\sigma_V$ correlations for different CDM cosmologies and compared the predicted correlations with the observed properties of a sample of low-redshift halos ranging in size from dwarf spheroidal galaxies to galaxy clusters. Our predictions are generally consistent with the data, with preference for the currently-favored, flat $\\Lambda$CDM model. Such a comparison serves to test the basic CDM paradigm while constraining the background cosmology and the power-spectrum of primordial density fluctuations, including larger wavenumbers than have previously been constrained.",
  "revisions": [
    {
      "version": "v2",
      "updated": "2001-12-21T15:15:38.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "dark matter halos",
      "phase-space densities",
      "cosmological implications",
      "correlation",
      "cdm model"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 575818
    }
  }
}