{
  "abstract": "Eclipse mapping is a well-established technique for constraining the spatial emission of hot Jupiter exoplanets. Brown dwarfs in ultra-short orbits around white dwarfs are an analog to hot Jupiters that can only ever be eclipsed within a limited range of latitudes. We adapt the eigenmapping method to disentangle the signals from the ever- and never-occulted regions. The result of this signal separation is a super-position of map structures, yielding sharp boundaries at the occultation region. We introduce a model that penalizes the harmonic complexity of the model map with Tikhonov regularization, whose parameters are tuned to reproduce the fit quality of the eigenmapping model. We use JWST NIRSpec/PRISM full-orbit observations of the eclipsing WD 1202-024 system as a template to construct and run injection-recovery tests on simulated light curves, isolating both latitudinal structures as well as emission from a physically-realistic general circulation model (GCM). In the latter, the narrow equatorial jet driven by the BD's rapid rotation manifests as an eclipse depth asymmetry, which our model reproduces as a latitude-dependent phase offset. Such a model, however, is only statistically preferred at approximately $3 \\times$ the signal-to-noise ratio of the JWST data. When fitting to the actual JWST data of WD 1202, the full-phase eigenbasis model is statistically preferred. However, the resulting model map of WD 1202 B does not resemble the GCM predictions, with a concentrated day-side hotspot at the sub-stellar point with an angular size $\\approx 15^\\circ$. Interpreting this result more carefully requires follow-up work to disentangle systematics from true emission signals. This model framework provides a means to detect emission features from these rare types of eclipses, and ultimately to test predictions of models of atmospheric circulation across hot Jupiters and their BD analogs.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.36141",
  "author_total": 12,
  "authors": [
    {
      "name": "Arthur D. Adams"
    },
    {
      "name": "Yifan Zhou"
    },
    {
      "name": "Daniel Apai"
    },
    {
      "name": "Daphne Broski-Laing"
    },
    {
      "name": "Sarah L. Casewell"
    },
    {
      "name": "Jenni R. French"
    },
    {
      "name": "L. C. Mayorga"
    },
    {
      "name": "Lael Shin"
    },
    {
      "name": "Xianyu Tan"
    },
    {
      "name": "Ben W. P. Lew"
    },
    {
      "name": "Joshua D. Lothringer"
    },
    {
      "name": "Vivien Parmentier"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/baea0zj0qedz6.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.36141",
  "fulltext_url": null,
  "id": "baea0zj0qedz6",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.36141",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.SR"
    ],
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7224130377",
  "pdf_url": "https://arxiv.org/pdf/2610.36141",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/baea0zj0qedz6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:50Z",
      "native_id": "2610.36141",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.36141"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.SR",
      "subfield": "stellar"
    }
  ],
  "title": "A Model to Map Brown Dwarf Companions to White Dwarfs in Partial Secondary Eclipse",
  "title_text": "A Model to Map Brown Dwarf Companions to White Dwarfs in Partial Secondary Eclipse",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:50Z",
  "url": "https://research.draconitic.com/paper/baea0zj0qedz6",
  "venue": "arXiv",
  "versions": []
}