{
  "abstract": "Hoag-type galaxies contain a smooth central core surrounded by a detached outer ring, but their rarity has limited previous studies mainly to individual systems. We identify thirty galaxies with apparent Hoag-type morphology in DESI imaging by visually inspecting two machine-learning ring-galaxy catalogues and analyse their core and ring properties using DESI Legacy Imaging Surveys $g$, $r$, and $z$ images. We measure the rings after subtracting two-dimensional core models and compare the cores with matched SDSS galaxies. The cores lie predominantly on the red sequence, whereas the rings span a broader colour range extending toward the blue cloud. The cores broadly follow early-type mass scaling relations, but their mass-matched distributions tend towards slightly bluer colours, smaller sizes, higher stellar-mass surface densities, and lower concentrations and Sérsic indices. Of the 16 systems with SDSS group information, 14 (87.5 per cent) are centrals, compared with $\\sim64\\%$ in the mass-matched early-type control sample. The halo-mass and large-scale overdensity distributions become much more similar after central--satellite status is also matched. Ring stellar-mass surface density and normalized width decrease with increasing core-plus-inner-halo to ring mass ratio. Most core $R_{90}$ values lie inside the outermost stable circular orbit of a simplified core-plus-ring model, while the rings frequently extend across its unstable interval. The slightly bluer core colours, lower concentrations, and lower Sérsic indices suggest a possible secular contribution, but the compact, dense cores imply more complex structural assembly than a simple diffuse-pseudobulge origin. The high central fraction may favour gas retention and ring survival by reducing satellite-specific environmental processing. The diversity of ring properties nevertheless leaves room for multiple formation pathways.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.39629",
  "author_total": 2,
  "authors": [
    {
      "name": "Jingshuo Yang"
    },
    {
      "name": "Cheng Li"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dw4h8q7k6dyja.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.39629",
  "fulltext_url": null,
  "id": "dw4h8q7k6dyja",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.39629",
  "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"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.39629",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dw4h8q7k6dyja.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:23Z",
      "native_id": "2610.39629",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.39629"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Hoag-type Galaxies: A Photometric Study of the Cores and Rings of Thirty Systems from the DESI Legacy Survey",
  "title_text": "Hoag-type Galaxies: A Photometric Study of the Cores and Rings of Thirty Systems from the DESI Legacy Survey",
  "type": "preprint",
  "updated_at": "2026-11-04T15:20:51Z",
  "url": "https://research.draconitic.com/paper/dw4h8q7k6dyja",
  "venue": "arXiv",
  "versions": []
}