{
  "abstract": "We report the Atacama Large Millimeter/submillimeter Array observations of 1.3 mm continuum, C$^{18}$O ($J=2$$-$$1$), and N$_{2}$D$^{+}$ ($J=3$$-$$2$) toward the millimeter multi-system MMS 2 in the Orion Molecular Cloud-3 region, at an angular resolution of 1.59\" ($\\sim$620 au). MMS 2 is in the flat-spectrum phase, with its protostars in the late stage of the main accretion phase. We detect the centrally condensed structures traced by C$^{18}$O emission associated with the 1.3 mm continuum sources MMS 2-North and MMS 2-South, which are spatially resolved and unresolved, respectively. The estimated diameter and mass of the centrally condensed structure associated with MMS 2-North are 1.64\" ($\\sim$640 au) and 3.0$\\times$10$^{-4}$M$_{\\odot}$, respectively. We also detect an extended structure traced by C$^{18}$O emission associated the circumbinary envelope at scale of 5.70\" ($\\sim$2240 au) with an estimated gas mass of 1.4$\\times$10$^{-2}$$M_{\\odot}$. In addition, we detect a filamentary structure traced by N$_2$D$^+$ emission to the south of MMS 2, which is spatially offset from the C$^{18}$O emission. This offset may be attributed to the influence of the warm surrounding environment.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.09897",
  "author_total": 3,
  "authors": [
    {
      "name": "Yuhua Liu"
    },
    {
      "name": "Satoko Takahashi"
    },
    {
      "name": "Masahiro N. Machida"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/62g9n7wh5yyb7.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.09897",
  "fulltext_url": null,
  "id": "62g9n7wh5yyb7",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.09897",
  "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": null,
  "pdf_url": "https://arxiv.org/pdf/2609.09897",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-09",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/62g9n7wh5yyb7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:12Z",
      "native_id": "2609.09897",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.09897"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The Dense Gas Structures Around MMS 2/OMC-3 Traced by C$^{18}$O Emission",
  "title_text": "The Dense Gas Structures Around MMS 2/OMC-3 Traced by C^18O Emission",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:12Z",
  "url": "https://research.draconitic.com/paper/62g9n7wh5yyb7",
  "venue": "arXiv",
  "versions": []
}