{
  "id": "1204.5816",
  "version": "v1",
  "published": "2012-04-26T02:45:04.000Z",
  "updated": "2012-04-26T02:45:04.000Z",
  "title": "Discovery of Multiple Shells Around the Planetary Nebula IC 418",
  "authors": [
    "Gerardo Ramos-Larios",
    "Roberto Vazquez",
    "Martin A. Guerrero",
    "Lorenzo Olguin",
    "R. A. Marquez-Lugo",
    "Hector Bravo-Alfaro"
  ],
  "comment": "9 pages, 5 figures, accepted for publication in MNRAS",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "We have analysed optical, near-, and mid-IR images of the bright planetary nebula (PN) IC 418. These images probe unambiguously for the first time a number of low surface brightness structures and shells around the bright main nebula, including radial filaments or rays, a system of three concentric rings, and two detached haloes with sizes ~ 150\" and 220\"\\times250\", respectively. The main nebula is slightly off-centered with respect to the elliptical outer halo. The time-lapse between the two haloes is 10,000-50,000 yr, whereas the time-lapse between the three concentric rings is ~ 630 yr. We emphasize the advantages of near- and mid-IR imaging for the detection of faint structures and shells around optically bright nebulae.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-04-26T02:45:04.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "planetary nebula ic",
      "multiple shells",
      "concentric rings",
      "low surface brightness structures",
      "bright planetary nebula"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1111/j.1365-2966.2012.21165.x",
      "journal": "Monthly Notices of the Royal Astronomical Society",
      "year": 2012,
      "month": "Jul",
      "volume": 423,
      "number": 4,
      "pages": 3753
    },
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1112517,
      "adsabs": "2012MNRAS.423.3753R"
    }
  }
}