{
  "abstract": "Many Fermi Large Area Telescope (LAT) sources remain unassociated. Some may be extended sources represented by multiple catalog entries, as found for HESS J1813-178. We search for clusters of unassociated Fermi-LAT sources and test whether single extended-source models describe them better than multiple catalog sources. We applied DBSCAN to 4FGL sources with a linking scale of $0.3^\\circ$ over 5 GeV-1 TeV. Each cluster contains at least one unassociated source and up to one extended or point-like associated source from selected categories, including pulsars, pulsar wind nebulae and supernova remnants. Using Fermipy, we compared extended- and multiple-source models and characterized each candidate spectrally and morphologically, focusing on the Galactic plane. We identified 48 clusters containing 124 sources, each with at least one unassociated source. For all 8 clusters passing our quality selection, an extended-source model is statistically preferred. At linking scales of $0.4^\\circ$ and $0.5^\\circ$, all 8 clusters retain their core sources. Cross-matches with the Second Fermi Galactic Extended Sources Catalog (2FGES) and the HESS Galactic Plane Survey (HGPS) showed that 5 clusters overlap known extended sources. The other 3 clusters, including one cluster with a morphology dependent on the interstellar emission model, have no counterpart in either catalog and are new extended-source candidates. Spatial clustering combined with likelihood-based model comparison can uncover extended sources missed in the Fermi-LAT catalog and complements existing searches.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "Journal reference: A&A 713, A92 (2026)",
  "arxiv": "2607.12776",
  "author_total": 5,
  "authors": [
    {
      "name": "Giovanni Cozzolongo"
    },
    {
      "name": "Alison M. W. Mitchell"
    },
    {
      "name": "Samuel T. Spencer"
    },
    {
      "name": "Dmitry V. Malyshev"
    },
    {
      "name": "Tim Unbehaun"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1x1e9fm2xw0q1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2607.12776",
  "fulltext_url": null,
  "id": "1x1e9fm2xw0q1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2607.12776",
  "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.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2607.12776",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-21",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1x1e9fm2xw0q1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:19Z",
      "native_id": "2607.12776",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2607.12776"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Identifying potentially missed extended sources in the Fermi-LAT 4FGL Catalog using clustering analysis",
  "title_text": "Identifying potentially missed extended sources in the Fermi-LAT 4FGL Catalog using clustering analysis",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:19Z",
  "url": "https://research.draconitic.com/paper/1x1e9fm2xw0q1",
  "venue": "arXiv",
  "versions": [
    {
      "doi": "10.1051/0004-6361/202660645",
      "pid": null,
      "relation": "published-as",
      "title": null,
      "venue": null
    }
  ]
}