{
  "id": "1811.09349",
  "version": "v1",
  "published": "2018-11-23T03:08:57.000Z",
  "updated": "2018-11-23T03:08:57.000Z",
  "title": "Very High-Energy Emission from the Direct Vicinity of Rapidly Rotating Black Holes",
  "authors": [
    "Kouichi Hirotani"
  ],
  "comment": "Invited review article, published in Radio Galaxies at TeV Energies, special issue of Galaxies; 37 pages, 18 figures",
  "journal": "Galaxies 2018, 6, 122",
  "doi": "10.3390/galaxies6040122",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "When a black hole accretes plasmas at very low accretion rate, an advection-dominated accretion flow (ADAF) is formed. In an ADAF, relativistic electrons emit soft gamma-rays via Bremsstrahlung. Some MeV photons collide with each other to materialize as electron-positron pairs in the magnetosphere. Such pairs efficiently screen the electric field along the magnetic field lines, when the accretion rate is typically greater than 0.03-0.3% of the Eddington rate. However, when the accretion rate becomes smaller than this value, the number density of the created pairs becomes less than the rotationally induced Goldreich-Julian density. In such a charge-starved magnetosphere, an electric field arises along the magnetic field lines to accelerate charged leptons into ultra-relativistic energies, leading to an efficient TeV emission via an inverse-Compton (C) process, spending a portion of the extracted hole's rotational energy. In this review, we summarize the stationary lepton accelerator models in black hole magnetospheres. We apply the model to super-massive black holes and demonstrate that nearby low-luminosity active galactic nuclei are capable of emitting detectable gamma-rays between 0.1 and 30 TeV with the Cherenkov Telescope Array.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2018-11-23T03:08:57.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "rapidly rotating black holes",
      "direct vicinity",
      "high-energy emission",
      "low-luminosity active galactic nuclei",
      "accretion rate"
    ],
    "tags": [
      "review article",
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 37,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}