{
  "id": "0909.4651",
  "version": "v1",
  "published": "2009-09-25T09:59:49.000Z",
  "updated": "2009-09-25T09:59:49.000Z",
  "title": "Detection of Gamma Rays From a Starburst Galaxy",
  "authors": [
    "The HESS Collaboration",
    "F. Acero"
  ],
  "comment": "24 pages, 8 figures, published in Science Express, see: http://www.sciencemag.org/cgi/content/abstract/1178826",
  "doi": "10.1126/science.1178826",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~ 10^15 eV. We report the detection of gamma rays -- tracers of such cosmic rays -- from the starburst galaxy NGC 253 using the H.E.S.S. array of imaging atmospheric Cherenkov telescopes. The gamma-ray flux above 220 GeV is F = (5.5 +/- 1.0stat +/- 2.8sys) x 10^-13 ph. s-1 cm-2, implying a cosmic-ray density about three orders of magnitude larger than that in the center of the Milky Way. The fraction of cosmic-ray energy channeled into gamma rays in this starburst environment is 5 times larger than that in our Galaxy.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2009-09-25T09:59:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "gamma rays",
      "accelerate energetic cosmic rays",
      "imaging atmospheric cherenkov telescopes",
      "starburst galaxy ngc",
      "cosmic-ray density"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "journal": "Science",
      "year": 2009,
      "month": "Nov",
      "volume": 326,
      "number": 5956,
      "pages": 1080
    },
    "note": {
      "typesetting": "TeX",
      "pages": 24,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 832157,
      "adsabs": "2009Sci...326.1080A"
    }
  }
}