{
  "id": "1104.4312",
  "version": "v1",
  "published": "2011-04-21T16:45:52.000Z",
  "updated": "2011-04-21T16:45:52.000Z",
  "title": "High resolution spectroscopy of Pluto's atmosphere: detection of the 2.3 $μ$m CH$_4$ bands and evidence for carbon monoxide",
  "authors": [
    "E. Lellouch",
    "C. de Bergh",
    "B. Sicardy",
    "H. U. Käufl",
    "A. Smette"
  ],
  "comment": "Astronomy and Astrophysics Letters, in press",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "The goal is to determine the composition of Pluto's atmosphere and to constrain the nature of surface-atmosphere interactions. We perform high--resolution spectroscopic observations in the 2.33--2.36 $\\mu$m range, using CRIRES at the VLT. We obtain (i) the first detection of gaseous methane in this spectral range, through lines of the $\\nu_3$ + $\\nu_4$ and $\\nu_1$ + $\\nu_4$ bands (ii) strong evidence (6-$\\sigma$ confidence) for gaseous CO in Pluto. For an isothermal atmosphere at 90 K, the CH$_4$ and CO column densities are 0.75 and 0.07 cm-am, within factors of 2 and 3, respectively. Using a physically--based thermal structure model of Pluto's atmosphere also satisfying constraints from stellar occultations, we infer CH$_4$ and CO mixing ratios q$_{CH_4}$= 0.6$^{+0.6}_{-0.3}$% (consistent with results from the 1.66 $\\mu$m range) and q$_{CO}$ = 0.5$^{+1}_{-0.25}$$\\times10^{-3}$. The CO atmospheric abundance is consistent with its surface abundance. As for Triton, it is probably controlled by a thin, CO-rich, detailed balancing layer resulting from seasonal transport and/or atmospheric escape.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2011-04-21T16:45:52.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high resolution spectroscopy",
      "plutos atmosphere",
      "carbon monoxide",
      "perform high-resolution spectroscopic observations",
      "physically-based thermal structure model"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1051/0004-6361/201116954",
      "journal": "Astronomy and Astrophysics",
      "year": 2011,
      "month": "Jun",
      "volume": 530
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 896916,
      "adsabs": "2011A&A...530L...4L"
    }
  }
}