{
  "abstract": "Molecular ices are a primary reservoir of volatile C, O, and N in star-forming environments, tracing the chemical pathway from molecular clouds to planet-forming disks. SPHEREx provides contiguous 0.75--5~$μ$m all-sky spectrophotometry for vastly larger samples than are accessible to JWST, enabling population-scale ice demographics for the first time. We present a search for ice signatures in SPHEREx spectra of 20{,}292 young stellar objects (age $<20$~Myr) drawn from the Gaia-based kinematic catalog of Kounkel \\& Covey 2019. Using laboratory templates for the spectral signatures of H$_2$O (3.05~$μ$m), CO$_2$ (4.27~$μ$m), and CO (4.67~$μ$m), we identify 746 H$_2$O ice candidates, including 131 high-confidence H$_2$O+CO$_2$ detections and 22 with additional corroborating CO absorption. When binning by age, we find that the H$_2$O$+$CO$_2$ detection rate declines by an order of magnitude between $\\lesssim$3~Myr and $\\sim$5~Myr, suggesting a chemical or physical evolutionary trend. Candidates concentrate toward high-extinction sightlines ($A_G \\gtrsim 2.5$~mag) and embedded SED morphologies, consistent with the idea of envelope dispersal and photodesorption depleting detectable ice mantles within the first few million years of pre-main-sequence evolution. This catalog provides a homogeneous demographic baseline and a prioritized target list for JWST follow-up.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.38043",
  "author_total": 5,
  "authors": [
    {
      "name": "J. Serna"
    },
    {
      "name": "S. P. Matt"
    },
    {
      "name": "M. McClure"
    },
    {
      "name": "M. Kounkel"
    },
    {
      "name": "C. G. Roman-Zuñiga"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/21pe31knqwdfj.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.38043",
  "fulltext_url": null,
  "id": "21pe31knqwdfj",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.38043",
  "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.SR"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2610.38043",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-27",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/21pe31knqwdfj.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:36:23Z",
      "native_id": "2610.38043",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.38043"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "Evolutionary Demographics of Molecular Ice Mantles in Young Stars with SPHEREx",
  "title_text": "Evolutionary Demographics of Molecular Ice Mantles in Young Stars with SPHEREx",
  "type": "preprint",
  "updated_at": "2026-11-01T12:20:44Z",
  "url": "https://research.draconitic.com/paper/21pe31knqwdfj",
  "venue": "arXiv",
  "versions": []
}