{
  "id": "1504.04030",
  "version": "v1",
  "published": "2015-04-15T20:06:12.000Z",
  "updated": "2015-04-15T20:06:12.000Z",
  "title": "An X-ray variable absorber within the Broad Line Region in Fairall 51",
  "authors": [
    "Jiri Svoboda",
    "Tobias Beuchert",
    "Matteo Guainazzi",
    "Anna Lia Longinotti",
    "Enrico Piconcelli",
    "Joern Wilms"
  ],
  "comment": "12 pages, 9 figures, accepted to A&A",
  "categories": [
    "astro-ph.GA",
    "astro-ph.HE"
  ],
  "abstract": "Fairall 51 is a polar-scattered Seyfert 1 galaxy, a type of active galaxies believed to represent a bridge between unobscured type-1 and obscured type-2 objects. Fairall 51 has shown complex and variable X-ray absorption but only little is known about its origin. In our research, we observed Fairall 51 with the X-ray satellite Suzaku in order to constrain a characteristic time-scale of its variability. We performed timing and spectral analysis of four observations separated by 1.5, 2 and 5.5 day intervals. We found that the 0.5-50 keV broadband X-ray spectra are dominated by a primary power-law emission (with the photon index ~ 2). This emission is affected by at least three absorbers with different ionisations (log(xi) ~ 1-4). The spectrum is further shaped by a reprocessed emission, possibly coming from two regions -- the accretion disc and a more distant scattering region. The accretion disc emission is smeared by the relativistic effects, from which we measured the spin of the black hole as a ~ 0.8 (+-0.2). We found that most of the spectral variability can be attributed to the least ionised absorber whose column density changed by a factor of two between the first (highest-flux) and the last (lowest-flux) observation. A week-long scale of the variability indicates that the absorber is located at the distance ~ 0.05 pc from the centre, i.e., in the Broad Line Region.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-04-15T20:06:12.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "broad line region",
      "x-ray variable absorber",
      "kev broadband x-ray spectra",
      "primary power-law emission",
      "x-ray satellite suzaku"
    ],
    "publication": {
      "doi": "10.1051/0004-6361/201425453"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 12,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1360249
    }
  }
}