{
  "id": "1605.06777",
  "version": "v1",
  "published": "2016-05-22T12:11:09.000Z",
  "updated": "2016-05-22T12:11:09.000Z",
  "title": "Constraints on the presence of SiO gas in the debris disk of HD 172555",
  "authors": [
    "T. L. Wilson",
    "R. Nilsson",
    "C. H. Chen",
    "C. M. Lisse",
    "M. Moerchen",
    "H. -U. Käufl",
    "A. Banzatti"
  ],
  "comment": "three figures",
  "categories": [
    "astro-ph.SR",
    "astro-ph.EP"
  ],
  "abstract": "We have carried out two sets of observations to quantify the properties of SiO gas in the unusual HD 172555 debris disk: (1) a search for the J=8-7 rotational transition from the vibrational ground state, carried out with the APEX sub-millimeter telescope and heterodyne receiver at 863 microns, and (2) a search at 8.3 microns for the P(17) ro-vibrational transition of gas phase SiO, carried out with VLT/VISIR with a resolution, $\\lambda/\\Delta\\lambda$, of 30000. The APEX measurement resulted in a 3.3 $\\sigma$ detection of an interstellar feature, but only an upper limit to emission at the radial velocity and linewidth expected from HD 172555. The VLT/VISIR result was also an upper limit. These were used to provide limits for the abundance of gas phase SiO, for a range of temperatures. The upper limit from our APEX detection, assuming an 8000\\,K primary star photospheric excitation, falls more than an order of magnitude below the self-shielding stability threshold derived by Johnson et al. (2012). Our results thus favor a solid-state origin for the 8.3 micron feature seen in the Spitzer IRS spectrum of the circumstellar excess emission, and the production of circumstellar O$^+$ and Si$^+$ by SiO UV photolysis. The implications of these estimates are explored in the framework of models of the HD\\,172555 circumstellar disk.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2016-05-22T12:11:09.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "debris disk",
      "sio gas",
      "gas phase sio",
      "upper limit",
      "constraints"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}