{
  "abstract": "Lithium is an excellent tracer of stellar mixing. We reconstruct the end of the main sequence lithium depletion pattern using the GALAH DR4 3D-NLTE lithium dataset for 22,442 stars, complemented by masses and subgiant lithium dilution factors inferred from YREC stellar models. We recover the two canonical features seen in clusters: a cool plateau ($\\mathrm{M_{[Fe/H]_{\\odot}}} \\sim 1.2 \\mathrm{M_\\odot}$) with a median $A(Li) = 2.42$, and a steep plunge into the lithium dip ($\\mathrm{M_{[Fe/H]_{\\odot}}} \\sim 1.35 \\mathrm{M_\\odot}$) dominated by upper limits at $A(Li) < 1.5$. Above the dip, our data reveal a striking new pattern with a wide range of abundances. We argue this reflects severe rotationally induced mixing in most stars, with lithium preserved in a minority where gravitational settling suppresses mixing. Lithium depletion with intrinsic dispersion is universal across the sample. Predicted and observed dilution trends agree well below the dip. For higher-mass stars, dilution corrections agree with standard models, but our upper envelope lies below open cluster values. We attribute this to a shallower lithium preservation zone and further evidence for gravitational settling and radiative levitation. We detect lithium in $\\approx25\\%$ of dip stars, whereas clusters show none; neither blurring of a narrow mass feature nor binary contamination fully explains this. The cool plateau is 0.8 dex below the solar meteoritic value across a wide range of $[Fe/H]$. After accounting for pre-main sequence depletion, the plateau is elevated at $\\geq [Fe/H]_{\\odot}$, possibly evidence for lithium production.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.22492",
  "author_total": 2,
  "authors": [
    {
      "name": "Vincent A. Smedile"
    },
    {
      "name": "Marc H. Pinsonneault"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5ww2t7fx1fdt2.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.22492",
  "fulltext_url": null,
  "id": "5ww2t7fx1fdt2",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.22492",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7222957565",
  "pdf_url": "https://arxiv.org/pdf/2610.22492",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5ww2t7fx1fdt2.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:30:32Z",
      "native_id": "2610.22492",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.22492"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "Let Sleeping Stars Li: Mapping Turnoff Lithium, the Lithium Dip, & Testing Standard Model Predictions in GALAH DR4 Subgiants",
  "title_text": "Let Sleeping Stars Li: Mapping Turnoff Lithium, the Lithium Dip, & Testing Standard Model Predictions in GALAH DR4 Subgiants",
  "type": "preprint",
  "updated_at": "2026-10-30T12:33:28Z",
  "url": "https://research.draconitic.com/paper/5ww2t7fx1fdt2",
  "venue": "arXiv",
  "versions": []
}