{
  "abstract": "Water and methanol are the fundamental constituents of interstellar and cometary ices: understanding their abundances in disks is therefore of high importance to reveal how this ice reservoir evolves across the timeline of star and planet formation. We present ALMA band 5 line emission observations of water and methanol in the warm Herbig disks of HD 100546 and IRS 48. While the IRS 48 disk is methanol-rich, water vapor is not detected, implying a high methanol-to-water column density ratio >0.2, possibly reflecting a distinct ice composition. Methanol and water are both detected in the HD 100546 disk, leading to a CH3OH/H2O ratio of ~0.02, consistent with the median of the cometary distribution and with the lower edge of the distribution of Young Stellar Objects. We suggest that the gas-phase methanol-to-water ratio in the HD 100546 disk directly reveals the ice reservoir subsequently sublimated in the warm disk stage. Moreover, we report a methyl formate-to-methanol ratio in the IRS 48 disk of ~0.2, consistent with the upper edge of the distribution of Young Stellar Objects. The methyl formate-to-methanol ratio in the HD 100546 disk is ~2, much higher than in younger and older sources, possibly reflecting a chemical enhancement of gas-phase methyl formate. We additionally constrain non-LTE conditions, optical depths, and emitting regions of the methanol lines in both disks. These results offer a new opportunity to probe the chemical trail of molecular complexity in the intermediate disk stage, bridging early and late phases of the star and planet formation history.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.22503",
  "author_total": 9,
  "authors": [
    {
      "name": "Luna Rampinelli"
    },
    {
      "name": "Stefano Facchini"
    },
    {
      "name": "Marta De Simone"
    },
    {
      "name": "Margot Leemker"
    },
    {
      "name": "Alice S. Booth"
    },
    {
      "name": "Myriam Benisty"
    },
    {
      "name": "Pietro Curone"
    },
    {
      "name": "Elizabeth Humphreys"
    },
    {
      "name": "Leonardo Testi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/76f29fbke9gdy.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.22503",
  "fulltext_url": null,
  "id": "76f29fbke9gdy",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.22503",
  "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.EP"
    ],
    [
      "openalex",
      "3103|Astrophysics and Star Formation Studies"
    ]
  ],
  "openalex": "W7222947796",
  "pdf_url": "https://arxiv.org/pdf/2610.22503",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/76f29fbke9gdy.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:30:32Z",
      "native_id": "2610.22503",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.22503"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    }
  ],
  "title": "An ALMA view on molecular complexity: water, methanol, and methyl formate in the HD 100546 and IRS 48 disks",
  "title_text": "An ALMA view on molecular complexity: water, methanol, and methyl formate in the HD 100546 and IRS 48 disks",
  "type": "preprint",
  "updated_at": "2026-10-30T12:33:28Z",
  "url": "https://research.draconitic.com/paper/76f29fbke9gdy",
  "venue": "arXiv",
  "versions": []
}