{
  "id": "1805.05379",
  "version": "v1",
  "published": "2018-05-14T18:52:36.000Z",
  "updated": "2018-05-14T18:52:36.000Z",
  "title": "The Evolution of Protoplanetary Disks: Probing the Inner Disk of Very Low Accretors",
  "authors": [
    "Thanawuth Thanathibodee",
    "Nuria Calvet",
    "Gregory Herczeg",
    "Cesar Briceno",
    "Catherine Clark",
    "Megan Reiter",
    "Laura Ingleby",
    "Melissa McClure",
    "Karina Mauco",
    "Jesus Hernandez"
  ],
  "comment": "13 pages, 3 figures. Accepted for publication in The Astrophysical Journal",
  "categories": [
    "astro-ph.SR",
    "astro-ph.EP",
    "astro-ph.GA"
  ],
  "abstract": "We report FUV, optical, and NIR observations of three T Tauri stars in the Orion OB1b subassociation with H$\\alpha$ equivalent widths consistent with low or absent accretion and various degrees of excess flux in the mid-infrared. We aim to search for evidence of gas in the inner disk in HST ACS/SBC spectra, and to probe the accretion flows onto the star using H$\\alpha$ and He I $\\lambda$10830 in spectra obtained at the Magellan and SOAR telescopes. At the critical age of 5 Myr, the targets are at different stages of disk evolution. One of our targets is clearly accreting, as shown by redshifted absorption at free-fall velocities in the He I line and wide wings in H$\\alpha$; however, a marginal detection of FUV H$_2$ suggests that little gas is present in the inner disk, although the spectral energy distribution indicates that small dust still remains close to the star. Another target is surrounded by a transitional disk, with an inner cavity in which little sub-micron dust remains. Still, the inner disk shows substantial amounts of gas, accreting onto the star at a probably low, but uncertain rate. The third target lacks both a He I line or FUV emission, consistent with no accretion or inner gas disk; its very weak IR excess is consistent with a debris disk. Different processes occurring in targets with ages close to the disk dispersal time suggest that the end of accretion phase is reached in diverse ways.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-05-14T18:52:36.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "inner disk",
      "low accretors",
      "protoplanetary disks",
      "little sub-micron dust remains",
      "equivalent widths consistent"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}