The 23rd Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun (Tokyo, June 15-19, 2026)
Published June 10, 2026 | Version v1
Poster Open

An R~100 5-14 μm Spectral Library of L0-T6 Dwarfs with the James Webb Space Telescope

Authors/Creators

  • 1. EDMO icon University of Western Ontario
  • 2. The University of Western Ontario
  • 3. Department of Astrophysics, American Museum of Natural History
  • 4. ROR icon Western University
  • 5. ROR icon Centro de Astrobiología
  • 6. Trottier Institute for Exoplanet Science
  • 7. ROR icon University of Edinburgh
  • 8. ROR icon University of California, San Diego
  • 9. AMERICAN MUSEUM OF NATURAL HISTORY
  • 10. ROR icon The University of Texas at Austin
  • 11. ROR icon Trinity College Dublin

Description

We present the results of a survey program with JWST’s MIRI LRS that obtained 5–14 μm R~100 spectra of twenty-three L0–T6 dwarfs. This spectral type range spans the formation, growth, and sedimentation of silicate condensate clouds, as well as the appearance of methane and ammonia in the atmospheres of brown dwarfs. The initial onset of silicate absorption at spectral type L0 as well as the evolution of this feature with spectral type are both examined in unprecedented detail. We detect 7.5–9.5 μm gas-phase SiO absorption for the first time in dwarf stars, with detections in M5.5–L2.5 dwarfs from combined Spitzer IRS and JWST spectra. This feature has previously been detected in K and M giants, however unlike in M stars, the SiO signature is weaker at lower gravities in L dwarfs. After accounting for contamination by candidate and probable binaries, we find that single field dwarfs are ~0.15–0.20 mag underluminous compared to existing empirical relations. The presented spectral library offers a spectrophotometrically calibrated basis for future interpretation of JWST MIRI spectra of brown dwarfs or of directly imaged or transiting exoplanets.

Files

Cool Stars Poster v2.pdf

Files (5.9 MB)

Name Size Download all
md5:eb96b03c9821b7f80ac970858db0f8a9
5.9 MB Preview Download

Additional details

Related works

Cites
Publication: 10.3847/1538-4357/acff66 (DOI)
Publication: 10.1088/0067-0049/201/2/19 (DOI)
Publication: 10.1088/0004-637X/810/2/158 (DOI)
Publication: 10.5281/zenodo.6600975 (DOI)

Dates

Submitted
2026-06-10