{
  "abstract": "Anisotropic ionizing radiation is a natural theoretical expectation for super-Eddington accretion in active galactic nuclei (AGNs), implying that the ionizing flux incident on the broad-line region (BLR) clouds differs from that measured along the observer's line of sight. Reverberation mapping studies have revealed systematically shortened time lags of the broad H$β$ emission line relative to continuum variations in super-Eddington AGNs, a phenomenon that can be naturally interpreted as a consequence of anisotropic ionizing continuum radiation. To further investigate this anisotropy, we perform a systematic analysis of the H$β$ line responsivity, defined as the ratio of the variability amplitude of H$β$ to that of the driving continuum, for both sub- and super-Eddington AGNs. By combining the effective responsivities measured relative to the driving continuum, after correcting for the continuum--emission-line delay, with photoionization calculations, we infer the ionizing radiation field received by their BLRs. We find that, in super-Eddington AGNs, the ionizing flux inferred from the H$β$ responsivity differs significantly from that observed along the line of sight, whereas the two are in closer agreement in sub-Eddington AGNs. These results provide compelling evidence for strong anisotropy of the incident ionizing radiation in super-Eddington AGNs. We conclude by discussing the broader implications of this anisotropy, including its potential relevance to the \"little red dots\" recently discovered by the James Webb Space Telescope.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.15255",
  "author_total": 3,
  "authors": [
    {
      "name": "Feng-Na Fang"
    },
    {
      "name": "Pu Du"
    },
    {
      "name": "Jian-Min Wang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0zj5v081sg1wh.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.15255",
  "fulltext_url": null,
  "id": "0zj5v081sg1wh",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.15255",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7221770591",
  "pdf_url": "https://arxiv.org/pdf/2610.15255",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-11",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0zj5v081sg1wh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:29:06Z",
      "native_id": "2610.15255",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.15255"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Anisotropic Radiation in Super-Eddington Active Galactic Nuclei: The Responsivity of Broad-Line Regions to Continuum Variability",
  "title_text": "Anisotropic Radiation in Super-Eddington Active Galactic Nuclei: The Responsivity of Broad-Line Regions to Continuum Variability",
  "type": "preprint",
  "updated_at": "2026-10-30T12:29:06Z",
  "url": "https://research.draconitic.com/paper/0zj5v081sg1wh",
  "venue": "arXiv",
  "versions": []
}