{
  "abstract": "We analyse black hole scaling relations for disk-dominated galaxies, and present evidence for secularly driven galaxy-black hole co-evolution. We do this observationally by looking at ``bulgeless'' galaxies, where the lack of a stellar bulge suggests a quiet merger history. We first compose a sample of 2,435 disk-dominated galaxies hosting optical broad line active galactic nuclei (AGN) from DESI data, and find a $M_{\\mathrm{BH}}$--$M_{*}$ scaling relation of $\\log(M_{\\mathrm{BH}})= - 3.7^{+0.3}_{-0.3} + 1.00^{+0.03}_{-0.03} \\log(M_*)$. From these, we identify 546 bulgeless galaxies hosting AGN, a factor of $\\gtrsim 5$ larger than pre-existing samples, and find they follow the same $M_{\\mathrm{BH}}$--$M_{*}$ relation as the general disk galaxy sample. Comparing the bulgeless galaxies to those with some bulge component, we find good agreement in the $M_{\\mathrm{BH}}$--$M_{*}$ relation (within $3 σ$), but disagreement in the $M_{\\mathrm{BH}}$--$M_{*, \\mathrm{bulge}}$ relation (at $>7 σ$). This is the opposite of what is expected from merger-driven co-evolution, suggesting secular growth is significant in establishing observed $M_{\\mathrm{BH}}$--$M_{*}$ scaling relations. Furthermore, in a control sample of early-type galaxies we find tentative evidence of increased AGN luminosity compared to the bulgeless sample, but no statistical difference in black hole mass. This suggests the assumed merger-dominated evolutionary history of early-type galaxies does not lead to significantly increased long-term BH growth. These results support numerous recent observational and theoretical studies which suggest secular processes fuel significant supermassive black hole growth and galaxy-black hole co-evolution.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.22434",
  "author_total": 11,
  "authors": [
    {
      "name": "Sophie M. Jewell"
    },
    {
      "name": "Rebecca J. Smethurst"
    },
    {
      "name": "Chris J. Lintott"
    },
    {
      "name": "Brooke D. Simmons"
    },
    {
      "name": "Ricarda S. Beckmann"
    },
    {
      "name": "Izzy L. Garland"
    },
    {
      "name": "Tobias Géron"
    },
    {
      "name": "Benne W. Holwerda"
    },
    {
      "name": "Karen L. Masters"
    },
    {
      "name": "Ragadeepika Pucha"
    },
    {
      "name": "Ashley Spindler"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bawdwpyhpsqp4.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.22434",
  "fulltext_url": null,
  "id": "bawdwpyhpsqp4",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.22434",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2609.22434",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-18",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bawdwpyhpsqp4.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2609.22434",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.22434"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Galaxy-SMBH co-evolution in 2,435 DESI disk galaxies and merger-free BH growth in bulgeless disks",
  "title_text": "Galaxy-SMBH co-evolution in 2,435 DESI disk galaxies and merger-free BH growth in bulgeless disks",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/bawdwpyhpsqp4",
  "venue": "arXiv",
  "versions": []
}