Directly imaged young exoplanets and brown dwarfs (BD) share similar characteristics, particularly during the L-T transition where atmospheres shift from cloudy to clear. This transition poses atmospheric modeling challenges due to clouds, affecting our understanding of exoplanet atmospheres. Recent James Webb Space Telescope (JWST) observations have provided precise broadband spectroscopic data on a planetary mass companion and BDs across this transition, highlighting atmospheric structures and cloud features. However, JWST’s low-dispersion spectra lack the detail necessary for thorough atmospheric analysis. To enhance this analysis, we propose high-dispersion follow-up observations with Subaru’s Infrared Doppler instrument (IRD) on the planetary mass companion VHS J1256b. This will allow for detailed examination of minor chemical species, precise temperature measurements, and mass inference crucial for accurate atmospheric modeling. By combining JWST’s broad observational range with Subaru’s high-resolution capabilities, we aim to improve our understanding of the atmospheres of subdwarfs during the L-T transition, offering insights into the atmospheric conditions of directly imaged exoplanets.
This document was translated from LATEX by HEVEA.