{
  "abstract": "We measure the projected radial distribution of blue-straggler-star (BSS) candidates in NGC 2158 using a Gaia DR3 membership catalog. The numerator and RGB/red-clump (RGB/RC) denominator are selected with the same thresholds, P mem ≥ 0.8 and RUWE < 1.2, yielding 38 BSS candidates and 197 reference stars. A boundary-free two-sample test shows that their observed radial distributions differ (two-sided KS D = 0.342, p = 8.0 × 10 ⁻⁴ ; Anderson–Darling p ≤ 0.001). The BSS candidates have a larger median radius (8 . ′ 45 versus 3 . ′ 39) and A + = − 0.26 1 − 0.110 + 0.112 , where the sign denotes a less concentrated BSS sample. However, five-fold out-of-fold tests of the archived classifier reveal strong CMD- and radius-dependent recovery: inside/outside 15′ the recovered fractions are 1/36 and 3/9 for BSS-like Hunt members, but 165/234 and 1/6 for RGB/RC-like members. Sparse outer reference templates prevent a stable inverse-completeness correction. Differential-reddening perturbations retain 14–24 outer candidates, but do not remove this dominant selection uncertainty. Two extinction-matched independent offset fields yield zero and one false full-pipeline candidate. We therefore report a significant difference in the selected catalog, not an intrinsic outer BSS excess. Spectroscopic membership and a selection function calibrated with independent, deeper photometry are required for a dynamical interpretation.",
  "abstract_shown": true,
  "affiliations": [
    "Yunnan Open University",
    "Guangzhou University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "affs": [
        0,
        1
      ],
      "name": "Huanbin 焕斌 Chi 迟",
      "orcid": "0000-0001-7343-7332"
    },
    {
      "affs": [
        0
      ],
      "name": "Jinli Lv"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6z2pvfqk5rgjp.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-3881/aea094",
  "fulltext_url": null,
  "id": "6z2pvfqk5rgjp",
  "issns": [
    "0004-6256",
    "1538-3881"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea094",
  "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|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7215094254",
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea094/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-01",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/6z2pvfqk5rgjp.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:14Z",
      "native_id": "10.3847/1538-3881/aea094",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea094"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "The Radial Distribution of Gaia-selected Blue-straggler Candidates in the Old Open Cluster NGC 2158",
  "title_text": "The Radial Distribution of Gaia-selected Blue-straggler Candidates in the Old Open Cluster NGC 2158",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:14Z",
  "url": "https://research.draconitic.com/paper/6z2pvfqk5rgjp",
  "venue": "The Astronomical Journal",
  "versions": []
}