{
  "id": "1808.08276",
  "version": "v1",
  "published": "2018-08-24T19:28:32.000Z",
  "updated": "2018-08-24T19:28:32.000Z",
  "title": "Galaxy formation in the Planck Millennium: the atomic hydrogen content of dark matter halos",
  "authors": [
    "C. M. Baugh",
    "Violeta Gonzalez-Perez",
    "Claudia D. P. Lagos",
    "Cedric G. Lacey",
    "John Helly",
    "Adrian Jenkins",
    "Carlos S. Frenk",
    "Andrew Benson",
    "Richard Bower",
    "Shaun Cole"
  ],
  "comment": "17 pages, submitted to MNRAS",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We present recalibrations of the GALFORM semi-analytical model of galaxy formation in a new N-body simulation with the Planck cosmology. The Planck Millennium simulation uses more than 128 billion particles to resolve the matter distribution in a cube of $800$ Mpc on a side, which contains more than 77 million dark matter haloes with mass greater than $2.12 \\times 10^{9} h^{-1} {\\rm M_{\\odot}}$ at the present day. Only minor changes to a very small number of model parameters are required in the recalibration. We present predictions for the atomic hydrogen content (HI) of dark matter halos, which is a key input into the calculation of the HI intensity mapping signal expected from the large-scale structure of the Universe. We find that the HI mass $-$ halo mass relation displays a clear break at the halo mass above which AGN heating suppresses gas cooling, $\\approx 3 \\times 10^{11} h^{-1} M_{\\rm \\odot}$. Below this halo mass, the HI content of haloes is dominated by the central galaxy; above this mass it is the combined HI content of satellites that prevails. We find that the HI mass - halo mass relation changes little with redshift up to $z=3$. The bias of HI sources shows a scale dependence that gets more pronounced with increasing redshift.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-08-24T19:28:32.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "dark matter halos",
      "atomic hydrogen content",
      "planck millennium",
      "galaxy formation",
      "halo mass relation changes little"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}