{
  "id": "1308.2041",
  "version": "v1",
  "published": "2013-08-09T06:46:15.000Z",
  "updated": "2013-08-09T06:46:15.000Z",
  "title": "Difference in the spatial distribution between H_2O and CO_2 ices in M82 found with AKARI",
  "authors": [
    "Mitsuyoshi Yamagishi",
    "Hidehiro Kaneda",
    "Daisuke Ishihara",
    "Shinki Oyabu",
    "Takashi Onaka",
    "Takashi Shimonishi",
    "Toyoaki Suzuki",
    "Young Chol Minh"
  ],
  "comment": "11 pages, 3 figures, 1 table, accepted for publication in the ApJ Letters",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "With AKARI, we obtain the spatially-resolved near-infrared (2.5 - 5.0 um) spectra for the nearby starburst galaxy M82. These spectra clearly show the absorption features due to interstellar ices. Based on the spectra, we created the column density maps of H_2O and CO_2 ices. As a result, we find that the spatial distribution of H_2O ice is significantly different from that of CO_2 ice; H_2O ice is widely distributed, while CO_2 ice is concentrated near the galactic center. Our result for the first time reveals variations in CO_2/H_2O ice abundance ratio on a galactic scale, suggesting that the ice-forming interstellar environment changes within a galaxy. We discuss the cause of the spatial variations in the ice abundance ratio, utilizing spectral information on the hydrogen recombination Br{\\alpha} and Br{\\beta} lines and the polycyclic aromatic hydrocarbon 3.3 um emission appearing in the AKARI near-infrared spectra.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2013-08-09T06:46:15.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "spatial distribution",
      "ice abundance ratio",
      "nearby starburst galaxy m82",
      "difference",
      "column density maps"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/2041-8205/773/2/L37",
      "journal": "The Astrophysical Journal",
      "year": 2013,
      "month": "Aug",
      "volume": 773,
      "number": 2
    },
    "note": {
      "typesetting": "TeX",
      "pages": 11,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1247230,
      "adsabs": "2013ApJ...773L..37Y"
    }
  }
}