{
  "id": "astro-ph/9911490",
  "version": "v2",
  "published": "1999-11-28T01:57:39.000Z",
  "updated": "1999-12-06T23:05:04.000Z",
  "title": "Silicate Emission in T Tauri Stars: Evidence for Disk Atmospheres?",
  "authors": [
    "Antonella Natta",
    "Michael R. Meyer",
    "Steven V. W. Beckwith"
  ],
  "comment": "Accepted for publication in the Astrophysical Journal.: 20 postscript pages including 5 figures and 2 tables. Minor typographical errors corrected",
  "doi": "10.1086/308787",
  "categories": [
    "astro-ph"
  ],
  "abstract": "We present low-resolution mid-infrared spectra of nine classical T Tauri stars associated with the Chamaeleon I dark cloud. The data were obtained with the PHOT-S instrument on-board the Infrared Space Observatory (ISO) in the two wavelength ranges 2.5-4.9 and 5.9-11.7 microns. All nine stars show evidence of silicate emission at 10 microns, which is the only prominent feature in the spectra. We discuss a model for the origin of these features in a hot optically-thin surface layer of the circumstellar disks surrounding the central young stars (i.e. a disk atmosphere). We report excellent agreement of our observations with predictions based upon this simple model for most stars in our sample, assuming that a mixture of amorphous silicates of radius ~< 1 microns is the dominant source of opacity. These observations support the notion that extended disk atmospheres contribute substantially to the mid-IR flux of young stars.",
  "revisions": [
    {
      "version": "v2",
      "updated": "1999-12-06T23:05:04.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "silicate emission",
      "tauri stars",
      "disk atmospheres contribute",
      "hot optically-thin surface layer",
      "phot-s instrument on-board"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 520499
    }
  }
}