{
  "abstract": "We measured the 198-310 GHz flux densities of 18 Class II protoplanetary disks in the Ophiuchus star-forming complex using the Submillimeter Array (SMA). The $\\sim$200-300 GHz spectral indices ($α_{200-300}$) of these disks are $2.3^{+0.2}_{-0.5}$. In this observed frequency range, emission properties of the Ophiuchus disks are very similar to the 48 spatially compact Class II disks in the Taurus-Auriga region observed in a previous SMA survey. Combining the Ophiuchus and Taurus-Auriga samples, the Pearson correlation coefficient between $α_{200-300}$ and the flux density at 250 GHz ($F_{250\\,\\mathrm{GHz}}$) is 0.27 ($p=0.02$). We do not find a convincing correlation between $α_{200-300}$ and the $R_{95\\%}$ radius of the disks. Our interpretation for the $α_{200-300}$ values being close to 2 in the spatially compact disks is that at $\\gtrsim 200$ GHz frequencies, the continuum emission in these disks is dominated by optically thick dust thermal emission, independent of $F_{250\\,\\mathrm{GHz}}$ and $R_{95\\%}$. As a result, the (sub)millimeter luminosity and the apparent disk size are positively correlated, which has been found in numerous resolved emission surveys of Class II disks. In young clusters with ages of $\\sim$1-2 Myr, Class II disks with smaller radii or lower (sub)millimeter luminosities are not necessarily those in which the dust mass budget has been consumed or dispersed.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.02619",
  "author_total": 7,
  "authors": [
    {
      "name": "Chia-Ying Chung"
    },
    {
      "name": "Hauyu Baobab Liu"
    },
    {
      "name": "Chuan-Yung Lin"
    },
    {
      "name": "Linjing Feng"
    },
    {
      "name": "Sean M. Andrews"
    },
    {
      "name": "Mark A. Gurwell"
    },
    {
      "name": "Melvyn Wright"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2g6eb1wznpaxz.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.02619",
  "fulltext_url": null,
  "id": "2g6eb1wznpaxz",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.02619",
  "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.EP"
    ],
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Astrophysics and Star Formation Studies"
    ]
  ],
  "openalex": "W7220438830",
  "pdf_url": "https://arxiv.org/pdf/2610.02619",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2g6eb1wznpaxz.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:26:45Z",
      "native_id": "2610.02619",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.02619"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "The 200-300 GHz Survey for 18 Class II Disks in the Ophiuchus Star-Forming Complex",
  "title_text": "The 200-300 GHz Survey for 18 Class II Disks in the Ophiuchus Star-Forming Complex",
  "type": "preprint",
  "updated_at": "2026-10-30T12:26:45Z",
  "url": "https://research.draconitic.com/paper/2g6eb1wznpaxz",
  "venue": "arXiv",
  "versions": []
}