{
  "abstract": "Changing-look active galactic nuclei (CL-AGN) have been proposed to follow an X-ray-binary-like, V-shaped relation between the optical/ultraviolet-to-X-ray spectral slope, αOX, and the Eddington ratio, λEdd ≡ Lbol/LEdd. We test this interpretation using CL-AGN selected from the Dark Energy Spectroscopic Instrument (DESI) and control samples matched to the eROSITA all-sky survey (eRASS). We find that the apparent positive correlation between αOX and the optical-continuum-based Eddington ratio, λEdd, opt, is not unique to CL-AGN, but also appears in matched non-changing-look samples. In broad-Hα AGN, our main statistical sample, this structure is largely driven by the known dependence of αOX on ultraviolet luminosity and by the covariance between the rest-frame 2500 Å luminosity, L2500, the black-hole mass, MBH, and λEdd, opt. When an X-ray-based Eddington ratio is used instead, the relation reverses sign because the X-ray luminosity, LX, enters the two axes with opposite signs. An apparent αOX–Eddington-ratio V-shape can therefore be induced by the luminosity estimator and is not a standalone accretion-state diagnostic. As a complementary test, we examine the eRASS effective photon index, Γeff, inferred from catalogue band fluxes. In broad-line AGN, it shows a weak positive association with the X-ray-independent optical Eddington ratio. However, the weaker hard-band trend depends on the null model and does not isolate coronal softening. These results motivate further X-ray spectroscopy, combined with independently estimated Eddington ratios, to test for intrinsic changes in the disk–corona system.",
  "abstract_shown": true,
  "affiliations": [
    "Durham University Centre for Extragalactic Astronomy, Department of Physics, , South Road, Durham, DH1 3LE ,",
    "National Astronomical Observatories, Chinese Academy of Sciences , 20A Datun Road, Chaoyang District, Beijing 100101 ,"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Wei-Jian Guo",
      "orcid": "0000-0001-9457-0589"
    },
    {
      "affs": [
        1
      ],
      "name": "Shuo Zhai"
    },
    {
      "affs": [
        1
      ],
      "name": "Zhu-Heng Yao"
    },
    {
      "affs": [
        1
      ],
      "name": "Huaqing Cheng",
      "orcid": "0000-0003-4200-9954"
    },
    {
      "affs": [
        1
      ],
      "name": "Jingwei Hu",
      "orcid": "0000-0002-0779-1947"
    },
    {
      "affs": [
        1
      ],
      "name": "Jun-Jie Jin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/apn4mk6t7ttdd.bib",
  "cited_by": 0,
  "doi": "10.1093/mnras/stag1920",
  "fulltext_url": null,
  "id": "apn4mk6t7ttdd",
  "issns": [
    "0035-8711",
    "1365-2966"
  ],
  "landing_url": "https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag1920/8910745",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3103|Astrophysical Phenomena and Observations"
    ]
  ],
  "openalex": "W7221061199",
  "pdf_url": "https://academic.oup.com/mnras/advance-article-pdf/doi/10.1093/mnras/stag1920/71881032/stag1920.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-12",
  "publisher": "Oxford University Press (OUP)",
  "ris": "https://research.draconitic.com/paper/apn4mk6t7ttdd.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:17Z",
      "native_id": "10.1093/mnras/stag1920",
      "source": "crossref",
      "url": "https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/stag1920/8910745"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "journal-openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. VII. Testing Disk–Corona Diagnostics with eROSITA",
  "title_text": "Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. VII. Testing Disk–Corona Diagnostics with eROSITA",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:17Z",
  "url": "https://research.draconitic.com/paper/apn4mk6t7ttdd",
  "venue": "Monthly Notices of the Royal Astronomical Society",
  "versions": []
}