{
  "id": "1512.00853",
  "version": "v1",
  "published": "2015-12-02T21:00:01.000Z",
  "updated": "2015-12-02T21:00:01.000Z",
  "title": "A Deep Search For Faint Galaxies Associated With Very Low-redshift C IV Absorbers: III. A Galaxy Sample Complete to 0.01 L* and Evidence for Environmental Effects",
  "authors": [
    "Joseph N. Burchett",
    "Todd M. Tripp",
    "Rongmon Bordoloi",
    "Jessica K. Werk",
    "J. Xavier Prochaska",
    "Jason Tumlinson",
    "C. N. A. Willmer",
    "John O'Meara",
    "Neal Katz"
  ],
  "comment": "19 pages, 16 figures. Submitted to ApJ, comments welcome!",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We employ a blindly selected sample of low-redshift C IV absorption systems identified in spectra from the Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS), combined with galaxy data from the Sloan Digital Sky Survey (SDSS), to study the metal-enriched circumgalactic medium (CGM) with ~100% completeness for galaxy luminosities L > 0.01 L* at z < 0.015. We find that galaxies are typically found at the C IV absorber redshifts within impact parameters rho < 200 kpc, with the nearest galaxy having L < 0.1 L* for 78% of the absorbers. The ubiquity of faint dwarfs in close proximity to the absorbers suggests that these galaxies affect the enrichment and physical conditions of massive-galaxy halos. However, a fraction of our sample (33%) arise well outside the virial radius of any nearby galaxy brighter than 0.01 L*. The detection rate for C IV absorption within the virial radius is mass dependent and is considerably higher for L >~0.1 L* galaxies (7/8) than for less luminous galaxies (1/10). We also find that the occurrence of C IV absorbers depends strongly on the broader environment: 67% (8/12) of galaxies with rho < 150 kpc in regions of low galaxy density (regions with fewer than ten 0.1 L* galaxies within 1 Mpc) have affiliated C IV absorption while none (0/9) of the galaxies in denser regions show C IV within rho < 150 kpc. The reduced detection rate of C IV in denser environments persists for massive group dark matter halos. In contrast, H I is pervasive in the CGM without regard to mass or environment, although some of these Ly-alpha absorbers could arise in unrelated intergalactic gas.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-12-02T21:00:01.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "galaxy sample complete",
      "faint galaxies",
      "deep search",
      "environmental effects",
      "low-redshift"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 19,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}