{
  "id": "1506.03333",
  "version": "v1",
  "published": "2015-06-10T14:47:27.000Z",
  "updated": "2015-06-10T14:47:27.000Z",
  "title": "First Detection of HCO$^+$ Absorption in the Magellanic System",
  "authors": [
    "Claire E. Murray",
    "Snežana Stanimirović",
    "N. M. McClure-Griffiths",
    "M. E. Putman",
    "H. S. Liszt",
    "Tony Wong",
    "P. Richter",
    "J. R. Dawson",
    "John M. Dickey",
    "Robert R. Lindner",
    "Brian L. Babler",
    "J. R. Allison"
  ],
  "comment": "Accepted for publication in ApJ. 6 pages, 2 figures, 2 tables",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We present the first detection of HCO$^+$ absorption in the Magellanic System. Using the Australia Telescope Compact Array (ATCA), we observed 9 extragalactic radio continuum sources behind the Magellanic System and detected HCO$^+$ absorption towards one source located behind the leading edge of the Magellanic Bridge. The detection is located at LSR velocity of $v=214.0 \\pm 0.4\\rm\\,km\\,s^{-1}$, with a full width at half maximum of $\\Delta v=4.5\\pm 1.0\\rm\\,km\\,s^{-1}$ and optical depth of $\\tau(\\rm HCO^+)=0.10\\pm 0.02$. Although there is abundant neutral hydrogen (HI) surrounding the sightline in position-velocity space, at the exact location of the absorber the HI column density is low, $<10^{20}\\rm\\,cm^{-2}$, and there is little evidence for dust or CO emission from Planck observations. While the origin and survival of molecules in such a diffuse environment remains unclear, dynamical events such as HI flows and cloud collisions in this interacting system likely play an important role.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-06-10T14:47:27.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "magellanic system",
      "first detection",
      "absorption",
      "australia telescope compact array",
      "extragalactic radio continuum sources"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}