{
  "abstract": "We present a study of stellar limb darkening using JWST transit observations of seven exoplanets orbiting FGK host stars, spanning 4200–6800 K. The wide wavelength coverage and high S/N of NIRISS/SOSS and NIRSpec/PRISM enable precise constraints on the wavelength-dependent limb darkening. Using Bayesian model selection, we find that the quadratic limb-darkening law is statistically preferred over higher-order laws for most FGK stars, recovers consistent intensity profiles for >95% of the stellar disk area, and introduces a minimal bias in the derived transit depths of only ∼14 ppm (1 σ ) for 6/7 targets. This contrasts with previous studies relying on stellar models. We compare the empirically derived quadratic coefficients to predictions from the PHOENIX, MPS-ATLAS, MURaM, and Stagger stellar atmosphere grids. We introduce a quadratic limb-darkening parameterization in terms of limb intensity ( ℓ ) and curvature at mid- μ ( δ ), finding that empirical FGK limb darkening is generally more linear than models predict ( δ ≲ 0.1). We identify wavelength-independent offsets between data and model quadratic coefficients, minimized by adopting μ min = 0.2 in intensity calculations; we attribute this in part to models overpredicting limb darkening near the limb where the plane-parallel approximation breaks down. For spherical PHOENIX models, we derive a μ rescaling method using a τ = 1 photospheric radius. With these corrections, residual offsets are minimized and all stellar models achieve statistically acceptable fits. We provide recommended limb-darkening offset priors for use in JWST transit analyses, enabling more accurate constraints on exoplanet transmission spectra while accounting for residual stellar model uncertainties.",
  "abstract_shown": true,
  "affiliations": [
    "Johns Hopkins University",
    "Space Telescope Science Institute",
    "University of Oxford",
    "University of Exeter",
    "Arizona State University",
    "Johns Hopkins APL",
    "Princeton University"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 14,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "David K. Sing",
      "orcid": "0000-0001-6050-7645"
    },
    {
      "affs": [
        1
      ],
      "name": "Joshua D. Lothringer",
      "orcid": "0000-0003-3667-8633"
    },
    {
      "affs": [
        1
      ],
      "name": "Jeff A. Valenti",
      "orcid": "0000-0003-3305-6281"
    },
    {
      "affs": [
        0
      ],
      "name": "Natalie H. Allen",
      "orcid": "0000-0002-0832-710X"
    },
    {
      "affs": [
        0
      ],
      "name": "Katherine A. Bennett",
      "orcid": "0000-0002-9030-0132"
    },
    {
      "affs": [
        1
      ],
      "name": "Carlos Gascón",
      "orcid": "0000-0001-5097-9251"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Mei Ting Mak",
      "orcid": "0000-0002-1624-3360"
    },
    {
      "affs": [
        0
      ],
      "name": "Patrick McCreery",
      "orcid": "0000-0003-0473-6931"
    },
    {
      "affs": [
        4
      ],
      "name": "Sagnick Mukherjee",
      "orcid": "0000-0003-1622-1302"
    },
    {
      "affs": [
        0
      ],
      "name": "Lakeisha M. Ramos Rosado",
      "orcid": "0000-0002-1056-3144"
    },
    {
      "affs": [
        0
      ],
      "name": "Stephen P. Schmidt",
      "orcid": "0000-0001-8510-7365"
    },
    {
      "affs": [
        5
      ],
      "name": "Kevin B. Stevenson",
      "orcid": "0000-0002-7352-7941"
    },
    {
      "affs": [
        0
      ],
      "name": "Daniel P. Thorngren",
      "orcid": "0000-0002-5113-8558"
    },
    {
      "affs": [
        6
      ],
      "name": "Le-Chris Wang",
      "orcid": "0000-0002-6379-3816"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5082kdjr2ykj8.bib",
  "cited_by": 0,
  "doi": "10.3847/1538-3881/aea21e",
  "fulltext_url": null,
  "id": "5082kdjr2ykj8",
  "issns": [
    "0004-6256",
    "1538-3881"
  ],
  "landing_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea21e",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7206194162",
  "pdf_url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea21e/pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": "American Astronomical Society",
  "ris": "https://research.draconitic.com/paper/5082kdjr2ykj8.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:14Z",
      "native_id": "10.3847/1538-3881/aea21e",
      "source": "crossref",
      "url": "https://iopscience.iop.org/article/10.3847/1538-3881/aea21e"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Stellar, planetary, and galactic studies",
      "subfield": "stellar"
    }
  ],
  "title": "A JWST Transiting Survey of FGK Stellar Limb Darkening: Empirical Evidence for Quadratic Laws and Atmospheric Model Comparisons",
  "title_text": "A JWST Transiting Survey of FGK Stellar Limb Darkening: Empirical Evidence for Quadratic Laws and Atmospheric Model Comparisons",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:14Z",
  "url": "https://research.draconitic.com/paper/5082kdjr2ykj8",
  "venue": "The Astronomical Journal",
  "versions": []
}