{
  "id": "1103.3946",
  "version": "v1",
  "published": "2011-03-21T09:04:01.000Z",
  "updated": "2011-03-21T09:04:01.000Z",
  "title": "Contribution of the Gamma-ray Loud Radio Galaxies Core Emissions to the Cosmic MeV and GeV Gamma-Ray Background Radiation",
  "authors": [
    "Yoshiyuki Inoue"
  ],
  "comment": "9 pages, accepted for publication in ApJ",
  "categories": [
    "astro-ph.HE",
    "astro-ph.CO"
  ],
  "abstract": "The Fermi gamma-ray satellite has recently detected gamma-ray emissions from radio galaxy cores. From these samples, we first examine the correlation between the luminosities at 5 GHz, L_{5GHz}, and at 0.1-10 GeV, L_{gamma}, of these gamma-ray loud radio galaxies. We find that the correlation is significant with L_{gamma} \\propto L_{5GHz}^{1.16} based on a partial correlation analysis. Using this correlation and the radio luminosity function (RLF) of radio galaxies, we further explore the contribution of gamma-ray loud radio galaxies to the unresolved extragalactic gamma-ray background (EGRB). The gamma-ray luminosity function is obtained by normalizing the RLF to reproduce the source count distribution of the Fermi gamma-ray loud radio galaxies. We find that gamma-ray loud radio galaxies will explain ~25% of the unresolved Fermi EGRB flux above 100 MeV and will also make a significant contribution to the EGRB in the 1-30 MeV energy band. Since blazars explain 22% of the EGRB above 100 MeV, radio loud active galactic nuclei (AGNs) population explains ~47% of the unresolved EGRB. We further make an interpretation on the origin of the EGRB. The observed EGRB spectrum at 0.2-100 GeV does not show an absorption signature by the extragalactic background light. Thus, the dominant population of the origin of EGRB at very high energy (>30 GeV) might be nearby gamma-ray emitting sources or sources with very hard gamma-ray spectrum.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2011-03-21T09:04:01.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "radio galaxy",
      "loud radio galaxies core emissions",
      "gamma-ray loud radio galaxies core",
      "gev gamma-ray background radiation"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/733/1/66",
      "journal": "The Astrophysical Journal",
      "year": 2011,
      "month": "May",
      "volume": 733,
      "number": 1,
      "pages": 66
    },
    "note": {
      "typesetting": "TeX",
      "pages": 9,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 893238,
      "adsabs": "2011ApJ...733...66I"
    }
  }
}