5 papers
The Y Dwarf Companion to the White Dwarf WD 0806-66: Resolving the Discrepancy Between Atmospheric and Evolutionary Models
S. K. Leggett, Pascal Tremblin
James Webb Space Telescope near- and mid-infrared spectroscopy has been published by Voyer et al. (2025) and Lew et al. (2026) for the Y dwarf which is a distant companion to the w…
The Coldest Known Y Dwarfs: Estimates of their Effective Temperatures
S. K. Leggett
For a decade there has been a factor of 2.5 gap in luminosity between the 275K WISE J085510.83-071442.5 (Luhman 2014) and all other Y dwarfs, with Teff >= 350K. Recently three obje…
Silicate Precursor Silane detected in Cold Low-Metallicity Brown Dwarf
Jacqueline K. Faherty, Aaron M. Meisner, Ben Burningham +28
Within 20 pc of the Sun there are currently 29 known cold brown dwarfs, sources with measured distances and an estimated effective temperature between that of Jupiter (170K) and ~5…
Exploration of the Near-Infrared Colors of Cold Y Dwarfs from the Ground and Space
S. K. Leggett, Mark W. Phillips, Pascal Tremblin
JWST has provided critical mid-infrared data for cold brown dwarfs. It has also provided low-resolution near-infrared spectra, and for faint sources these are the first spectra at…
Redshifting the Study of Cold Brown Dwarfs and Exoplanets: the Mid-Infrared Wavelength Region as an Indicator of Surface Gravity and Mass
S. K. Leggett, Pascal Tremblin
JWST is opening many avenues for exploration. For cold brown dwarfs and exoplanets, JWST has opened the door to the mid-infrared wavelength region, where such objects emit signific…