{
  "abstract": "A major unknown in late-stage galaxy evolution is what regulates the cold interstellar medium (ISM) after quenching, a question central to interpreting molecular gas, dust, and stellar content in quiescent galaxies (QGs) now probed by ALMA and JWST to $z\\sim7$. We present the first semi-analytic model that follows the coupled post-quenching evolution of dust, cold gas, and polycyclic aromatic hydrocarbons (PAHs), using flexible star-formation histories and a framework tracking small and large carbonaceous and silicate grains. At $z\\sim1$, we find that QGs of similar mass ($M_\\star\\sim8\\times10^{10} M_\\odot$), stellar-population age ($\\sim2$ Gyr), and cold gas fractions ($f_{\\rm gas}\\sim1$-$10\\%$), span $2$-$3$ dex in $M_{\\rm dust}/M_\\star$ and $M_{\\rm dust}/M_{\\rm gas}$, ranging from star-forming-like ratios to highly depleted dust states. The diversity arises from delayed dust injection by thermally pulsing asymptotic giant branch (TP-AGB) stars and ISM grain growth, which sustain dust enrichment for up to $\\sim2.5$ Gyr after quenching. Without these channels, the pre-quenching $M_{\\rm dust}$ falls below $10\\%$ of its initial value within $\\lesssim0.5$-$1$ Gyr, and twice as fast when AGN feedback is active. The imprint of post-quenching dust processing persists in substantial reservoirs of small carbonaceous grains, with PAH fractions of $\\sim2$-$3\\%$, even if the cold-dust budget falls below typical ALMA continuum detection limits ($M_{\\rm dust}/M_\\star\\lesssim10^{-4}$). Such signatures may remain detectable with JWST/MIRI at $μ$Jy depths, probing chemically enriched dust phases in otherwise ALMA-faint galaxies. Altogether, dust and PAHs provide independent probes of distinct stages of ISM evolution in QGs, rather than simply tracing the residual cold ISM of the preceding star-forming phase.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.27571",
  "author_total": 12,
  "authors": [
    {
      "name": "D. Donevski"
    },
    {
      "name": "A. Nanni"
    },
    {
      "name": "K. E. Whitaker"
    },
    {
      "name": "A. W. S. Man"
    },
    {
      "name": "A. Faisst"
    },
    {
      "name": "A. Lapi"
    },
    {
      "name": "I. García-Bernete"
    },
    {
      "name": "M. Romano"
    },
    {
      "name": "T. Petrushevska"
    },
    {
      "name": "G. Gururajan"
    },
    {
      "name": "G. Lorenzon"
    },
    {
      "name": "D. Narayanan"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6jhn6jmv5jv3c.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.27571",
  "fulltext_url": null,
  "id": "6jhn6jmv5jv3c",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.27571",
  "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",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7204762444",
  "pdf_url": "https://arxiv.org/pdf/2608.27571",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6jhn6jmv5jv3c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2608.27571",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.27571"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Dust and PAHs in late-stage galaxy evolution: Imprints of TP-AGB dust injection, grain growth and AGN feedback in high-z quiescent galaxies with JWST and ALMA",
  "title_text": "Dust and PAHs in late-stage galaxy evolution: Imprints of TP-AGB dust injection, grain growth and AGN feedback in high-z quiescent galaxies with JWST and ALMA",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/6jhn6jmv5jv3c",
  "venue": "arXiv",
  "versions": []
}