{
  "id": "astro-ph/9902377",
  "version": "v1",
  "published": "1999-02-26T16:05:00.000Z",
  "updated": "1999-02-26T16:05:00.000Z",
  "title": "The distribution of absorbing column densities among Seyfert 2 galaxies",
  "authors": [
    "G. Risaliti",
    "R. Maiolino",
    "M. Salvati"
  ],
  "comment": "16 LaTeX pages+5 postscript figures, accepted by ApJ",
  "journal": "Astrophys.J. 522 (1999) 157-164",
  "doi": "10.1086/307623",
  "categories": [
    "astro-ph"
  ],
  "abstract": "We use hard X-ray data for an \"optimal\" sample of Seyfert 2 galaxies to derive the distribution of the gaseous absorbing column densities among obscured active nuclei in the local Universe. Of all Seyfert 2 galaxies in the sample, 75% are heavily obscured (N_H > 10^23 cm^-2) and about half are Compton thick (N_H > 10^24 cm^-2). Intermediate type 1.8-1.9 Seyferts are characterized by an average N_H much lower than \"strict\" Seyfert 2s. No correlation is found between N_H and the intrinsic luminosity of the nuclear source. This N_H distribution has important consequences for the synthesis of the cosmic X-ray background. Also, the large fraction of Compton thick objects implies that most of the obscuring gas is located within a radius of a few 10 pc from the nucleus.",
  "revisions": [
    {
      "version": "v1",
      "updated": "1999-02-26T16:05:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "distribution",
      "compton thick objects implies",
      "hard x-ray data",
      "cosmic x-ray background",
      "gaseous absorbing column densities"
    ],
    "tags": [
      "journal article",
      "famous paper"
    ],
    "note": {
      "typesetting": "LaTeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 495957
    }
  }
}