{
  "id": "0902.0122",
  "version": "v1",
  "published": "2009-02-01T10:41:58.000Z",
  "updated": "2009-02-01T10:41:58.000Z",
  "title": "HCO+ and HCN J=3-2 absorption toward the center of Centaurus A",
  "authors": [
    "Sebastien Muller",
    "Dinh-V-Trung"
  ],
  "comment": "Accepted for publication in ApJ",
  "journal": "Astrophys.J.696:176-181,2009",
  "doi": "10.1088/0004-637X/696/1/176",
  "categories": [
    "astro-ph.CO"
  ],
  "abstract": "We have investigated the presence of dense gas toward the radio source Cen A by looking at the absorption of the HCO+ and HCN (3-2) lines in front of the bright continuum source with the Submillimeter Array. We detect narrow HCO+ (3-2) absorption, and tentatively HCN (3-2), close to the systemic velocity. For both molecules, the J=3-2 absorption is much weaker than for the J=1-0 line. From simple excitation analysis, we conclude that the gas density is on the order of a few 10^4 cm^-3 for a column density N(HCO+)/dV of 3x10^12 cm^-2 km^-1 s and a kinetic temperature of 10 K. In particular, we find no evidence for molecular gas density higher than a few 10^4 cm^-3 on the line of sight to the continuum source. We discuss the implications of our finding on the nature of the molecular gas responsible for the absorption toward Cen A.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2009-02-01T10:41:58.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "absorption",
      "molecular gas density higher",
      "radio source cen",
      "simple excitation analysis",
      "bright continuum source"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "The Astrophysical Journal",
      "year": 2009,
      "month": "May",
      "volume": 696,
      "number": 1,
      "pages": 176
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 812292,
      "adsabs": "2009ApJ...696..176M"
    }
  }
}