{
  "id": "1103.5402",
  "version": "v3",
  "published": "2011-03-28T16:16:08.000Z",
  "updated": "2012-01-26T06:04:14.000Z",
  "title": "Infrared Spectral Energy Distribution of Galaxies in the AKARI All Sky Survey: Correlations with Galaxy Properties, and Their Physical Origin",
  "authors": [
    "Tomonori Totani",
    "Tsutomu T. Takeuchi",
    "Masahiro Nagashima",
    "Masakazu A. R. Kobayashi",
    "Ryu Makiya"
  ],
  "comment": "29 pages including 28 figures. matches the published version (PASJ 2011 Dec. 25 issue). The E-open option was chosen for this article, i.e., the official version available from PASJ site (http://pasj.asj.or.jp/v63/n6/630613/630613-frame.html) without restriction",
  "journal": "Pub. Astron. Soc. Jpn, 63, 1181-1206 (2011)",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "We have studied the properties of more than 1600 low-redshift galaxies by utilizing high-quality infrared flux measurements of the AKARI All-Sky Survey and physical quantities based on optical and 21-cm observations. Our goal is to understand the physics determining the infrared spectral energy distribution (SED). The ratio of the total infrared luminosity L_TIR, to the star-formation rate (SFR) is tightly correlated by a power-law to specific SFR (SSFR), and L_TIR is a good SFR indicator only for galaxies with the largest SSFR. We discovered a tight linear correlation for normal galaxies between the radiation field strength of dust heating, estimated by infrared SED fits (U_h), and that of galactic-scale infrared emission (U_TIR ~ L_TIR/R^2), where R is the optical size of a galaxy. The dispersion of U_h along this relation is 0.3 dex, corresponding to 13% dispersion in the dust temperature. This scaling and the U_h/U_TIR ratio can be explained physically by a thin layer of heating sources embedded in a thicker, optically-thick dust screen. The data also indicate that the heated fraction of the total dust mass is anti-correlated to the dust column density, supporting this interpretation. In the large U_TIR limit, the data of circumnuclear starbursts indicate the existence of an upper limit on U_h, corresponding to the maximum SFR per gas mass of ~ 10 Gyr^{-1}. We find that the number of galaxies sharply drops when they become optically thin against dust-heating radiation, suggesting that a feedback process to galaxy formation (likely by the photoelectric heating) is working when dust-heating radiation is not self-shielded on a galactic scale. Implications are discussed for the M_HI-size relation, the Kennicutt-Schmidt relation, and galaxy formation in the cosmological context.",
  "revisions": [
    {
      "version": "v3",
      "updated": "2012-01-26T06:04:14.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "infrared spectral energy distribution",
      "sky survey",
      "galaxy properties",
      "physical origin",
      "high-quality infrared flux measurements"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1093/pasj/63.6.1181",
      "journal": "Publications of the Astronomical Society of Japan",
      "year": 2011,
      "month": "Dec",
      "volume": 63,
      "pages": 1181
    },
    "note": {
      "typesetting": "TeX",
      "pages": 29,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 894428,
      "adsabs": "2011PASJ...63.1181T"
    }
  }
}