{
  "id": "1306.1777",
  "version": "v1",
  "published": "2013-06-07T16:58:32.000Z",
  "updated": "2013-06-07T16:58:32.000Z",
  "title": "OH/IR stars and their superwinds as observed by the Herschel Space Observatory",
  "authors": [
    "K. Justtanont",
    "D. Teyssier",
    "M. J. Barlow",
    "M. Matsuura",
    "B. Swinyard",
    "L. B. F. M. Waters",
    "J. Yates"
  ],
  "comment": "10 pages with 11 figures Accepted for publication by Astronomy & Astrophysics",
  "categories": [
    "astro-ph.SR"
  ],
  "abstract": "Aim : In order to study the history of mass loss in extreme OH/IR stars, we observed a number of these objects using CO as a tracer of the density and temperature structure of their circumstellar envelopes. Method : Combining CO observations from the Herschel Space Observatory with those from the ground, we trace mass loss rates as a function of radius in five extreme OH/IR stars. Using radiative transfer modelling, we modelled the dusty envelope as well as the CO emission. The high-rotational transitions of CO indicate that they originate in a dense superwind region close to the star while the lower transitions tend to come from a more tenuous outer wind which is a result of the mass loss since the early AGB phase. Result : The models of the circumstellar envelopes around these stars suggest that they have entered a superwind phase in the past 200 - 500 years. The low 18O/17O (~ 0.1 compared to the solar abundance ratio of ~ 5) and 12C/13C (3-30 cf. the solar value of 89) ratios derived from our study support the idea that these objects have undergone hot-bottom burning and hence that they are massive M >= 5 solar-mass AGB stars.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2013-06-07T16:58:32.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "herschel space observatory",
      "extreme oh/ir stars",
      "dense superwind region close",
      "trace mass loss rates",
      "circumstellar envelopes"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1051/0004-6361/201321812",
      "journal": "Astronomy and Astrophysics",
      "year": 2013,
      "month": "Aug",
      "volume": 556
    },
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1237649,
      "adsabs": "2013A&A...556A.101J"
    }
  }
}