Sinking Silicates. I. Characterizing the Benchmark System Containing the T0 Brown Dwarf CWISEJ210640.16+250729.0 using JWST
Abstract In this study, we present the full (97.3% complete) 0.8–12.5 μ m spectral energy distribution (SED) of an L/T transition object, CWISE J210640.16+250729.0 (CW 2106), using the James Webb Space Telescope (JWST). We provide a full characterization of the host star’s elemental abundances and age. We empirically derive the bolometric luminosity (≈ −4.825 dex) of CW 2106, and obtain estimates of its mass ( M ≈ 50–62 M Jup ), radius ( R ≈ 0.83–0.87 R Jup ), effective temperature ( T eff ≈ 1213 K), and surface gravity ( log g ≈ 5.28 dex). We find the near-infrared (near-IR) spectrum (0.8–2.5 μ m) is best reproduced with cloudy atmospheric models while the mid-infrared (mid-IR) spectrum (5–12.5 μ m) is best reproduced with cloudless models. This suggests a cloud layer restricted to only the deepest observable parts of the atmosphere and is qualified by the lack of a 9 μ m silicate feature. Making use of the Mg/Si ratio of the primary, alongside thermochemical models, we predict the clouds in CW 2106 to be composed primarily of enstatite (MgSiO 3 ), removing ∼23% of the bulk oxygen out of the atmosphere. Future retrieval studies will be able to help investigate the existence and full impact of these cloud species.
Authors
- Jacqueline K. Faherty (ORCID: https://orcid.org/0000-0001-6251-0573)
- Johanna M. Vos (ORCID: https://orcid.org/0000-0003-0489-1528)
- Caprice L. Phillips (ORCID: https://orcid.org/0000-0001-5610-5328)
- Emily Calamari (ORCID: https://orcid.org/0000-0002-2682-0790)
- Niall Whiteford (ORCID: https://orcid.org/0000-0001-8818-1544)
- Channon Visscher (ORCID: https://orcid.org/0000-0001-6627-6067)
- Viktória Kecskeméthy (ORCID: https://orcid.org/0000-0002-9511-0901)
- John M. Brewer (ORCID: https://orcid.org/0000-0002-9873-1471)
- Jonathan Gagné (ORCID: https://orcid.org/0000-0002-2592-9612)
- Ben Burningham (ORCID: https://orcid.org/0000-0003-4600-5627)
- Marina E. Gemma (ORCID: https://orcid.org/0000-0002-8871-773X)
- Josefine Gaarn (ORCID: https://orcid.org/0000-0002-8916-2078)
- Genaro Suárez (ORCID: https://orcid.org/0000-0002-2011-4924)
- Austin James Rothermich (ORCID: https://orcid.org/0000-0003-4083-9962)
- Kelle L. Cruz (ORCID: https://orcid.org/0000-0002-1821-0650)
- Catherine Manea (ORCID: https://orcid.org/0000-0002-0900-6076)
- Eileen C. Gonzales (ORCID: https://orcid.org/0000-0003-4636-6676)
- Daniella Carolina Bardalez Gagliuffi (ORCID: https://orcid.org/0000-0001-8170-7072)
- Mark S. Marley
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2026-10-29
- DOI
- https://doi.org/10.3847/1538-4357/aea4b2
- Primary Topic
- Stellar, planetary, and galactic studies
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- National Aeronautics and Space Administration
- Space Telescope Science Institute