{
  "id": "1504.01844",
  "version": "v1",
  "published": "2015-04-08T06:59:48.000Z",
  "updated": "2015-04-08T06:59:48.000Z",
  "title": "Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$β$ Time Lags and Implications for Super-Eddington Accretion",
  "authors": [
    "Pu Du",
    "Chen Hu",
    "Kai-Xing Lu",
    "Ying-Ke Huang",
    "Cheng Cheng",
    "Jie Qiu",
    "Yan-Rong Li",
    "Yang-Wei Zhang",
    "Xu-Liang Fan",
    "Jin-Ming Bai",
    "Wei-Hao Bian",
    "Ye-Fei Yuan",
    "Shai Kaspi",
    "Luis C. Ho",
    "Hagai Netzer",
    "Jian-Min Wang"
  ],
  "comment": "53 pages, 12 figures, 7 tables, accepted for publication in The Astrophysical Journal",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO",
    "astro-ph.HE"
  ],
  "abstract": "We have completed two years of photometric and spectroscopic monitoring of a large number of active galactic nuclei (AGNs) with very high accretion rates. In this paper, we report on the result of the second phase of the campaign, during 2013--2014, and the measurements of five new H$\\beta$ time lags out of eight monitored AGNs. All five objects were identified as super-Eddington accreting massive black holes (SEAMBHs). The highest measured accretion rates for the objects in this campaign are $\\dot{\\mathscr{M}}\\gtrsim 200$, where $\\dot{\\mathscr{M}}= \\dot{M}_{\\bullet}/L_{\\rm Edd}c^{-2}$, $\\dot{M}_{\\bullet}$ is the mass accretion rates, $L_{\\rm Edd}$ is the Eddington luminosity and $c$ is the speed of light. We find that the H$\\beta$ time lags in SEAMBHs are significantly shorter than those measured in sub-Eddington AGNs, and the deviations increase with increasing accretion rates. Thus, the relationship between broad-line region size ($R_{_{\\rm H\\beta}}$) and optical luminosity at 5100\\AA, $R_{_{\\rm H\\beta}}-L_{5100}$, requires accretion rate as an additional parameter. We propose that much of the effect may be due to the strong anisotropy of the emitted slim-disk radiation. Scaling $R_{_{\\rm H\\beta}}$ by the gravitational radius of the black hole, we define a new radius-mass parameter ($Y$) and show that it saturates at a critical accretion rate of $\\dot{\\mathscr{M}}_c=6\\sim 30$, indicating a transition from thin to slim accretion disk and a saturated luminosity of the slim disks. The parameter $Y$ is a very useful probe for understanding the various types of accretion onto massive black holes. We briefly comment on implications to the general population of super-Eddington AGNs in the universe and applications to cosmology.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-04-08T06:59:48.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high accretion rates",
      "active galactic nuclei",
      "time lags",
      "supermassive black holes",
      "super-eddington accretion"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/806/1/22"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 53,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1358368
    }
  }
}