{
  "id": "1209.5365",
  "version": "v1",
  "published": "2012-09-24T18:57:49.000Z",
  "updated": "2012-09-24T18:57:49.000Z",
  "title": "New Maser Emission from Nonmetastable Ammonia in NGC 7538. III. Detection of the (10,6) Transition and a Velocity Gradient",
  "authors": [
    "Ian M. Hoffman"
  ],
  "comment": "6 pages, 5 figures, 1 table; emulateapj, accepted to ApJ; color figures only on arXiv",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "We present the first astronomical detection of the 14NH3 (J,K) = (10,6) line: nonthermal emission at several velocities in the Galactic star-forming region NGC 7538. Using the VLA we have imaged the (10,6) and (9,6) ammonia masers at several positions within NGC 7538 IRS 1. The individual sources have angular sizes < 0.1 arcseconds corresponding to brightness temperatures T_B > 1E6 K. We apply the pumping model of Brown & Cragg, confirming the conjecture that multiple ortho-ammonia masers can occur with the same value of K. The positions and velocities of the (10,6) and (9,6) masers are modeled as motion in a possible disk or torus and are discussed in the context of recent models of the region.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-09-24T18:57:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "velocity gradient",
      "maser emission",
      "nonmetastable ammonia",
      "transition",
      "galactic star-forming region ngc"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/759/1/76",
      "journal": "The Astrophysical Journal",
      "year": 2012,
      "month": "Nov",
      "volume": 759,
      "number": 1,
      "pages": 76
    },
    "note": {
      "typesetting": "TeX",
      "pages": 6,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1187760,
      "adsabs": "2012ApJ...759...76H"
    }
  }
}