{
  "annotation_id": "105a90f3-c6e2-4fcc-b998-0dfd23b17d6f",
  "date_created": "2026-02-17T05:53:24.168000Z",
  "date_modified": "2026-02-17T05:53:24.168000Z",
  "file_hash": "4538394512308f70942723ab91871a5c883ff6c32234b6158e06dc6a51dd4fdc",
  "private": false,
  "record": {
    "abstract": "Recently Quenched Ellipticals (RQEs) provide a valuable test case for disentangling intrinsic and environmental quenching, particularly because they are commonly classified as isolated central galaxies in low-mass halos. However, central/satellite assignments and isolation labels can vary across group catalogs, and such misclassifications can strongly bias physical interpretations. We present a uniform, physically motivated reassessment of the environments of 155 RQEs previously identified as centrals in an SDSS-based group catalog. We construct value-added neighbor catalogs via KD-tree searches and apply consistent thresholds in projected separation and line-of-sight velocity to (i) verify centrality, (ii) quantify isolation using a mass-ratio-based companion criterion, and (iii) identify potential pseudo-centrals via proximity to massive clusters. We find that 132/155 (85.2\\%) RQEs remain true centrals, while 23/155 (14.8\\%) are better interpreted as misidentified centrals with a more massive neighbor within $R_{\\rm proj}\\leq0.8$~Mpc and $\\Delta V\\leq250$~km~s$^{-1}$. Among the true centrals, 110/132 (83.3\\%) satisfy our isolation criterion, and only one system meets our pseudo-central definition, indicating that direct cluster-scale preprocessing is rare for RQE centrals. Using projected number density and surface stellar mass density, we show that misidentified and non-isolated systems occupy systematically denser regimes than isolated true centrals. These results imply that while most RQEs ($\\sim$71\\%) are consistent with predominantly internal quenching in genuinely isolated centrals, a non-negligible minority ($\\sim$29\\%) likely experienced environmentally influenced pathways at group scales.",
    "arxiv_id": "2601.09846",
    "authors": [
      "Deepak K. Deo"
    ],
    "categories": [
      "astro-ph.GA"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "title": "Are Recently Quenched Ellipticals Truly Isolated Centrals?",
    "url": "https://arxiv.org/abs/2601.09846",
    "version": "v1"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "09d91017-7896-4b28-8284-fe7c80ab2a3a",
    "id": "arXiv Dataset",
    "type": "Model",
    "variant": "snapshot-2026-01-17",
    "version": "0.1.0"
  },
  "user_id": 1000002
}