Observationally-Driven Atmospheric Modeling of Brown Dwarfs and Exoplanets

University Of Texas At Austin, Austin TX

Investigators

Abstract

Brown dwarfs are substellar objects, larger than what most consider to be ?planets,? but not quite massive enough to generate fusion in their cores. Their atmospheres, many of which have been detected, are thought to be similar to the atmospheres of exoplanets (which are much harder to detect directly). The team will use the results of this work to understand molecular composition and cloud formation in these atmospheres, and to identify weaknesses in current models (and point the way to better models). The eventual goal of this work is to refine our understanding of these atmospheres in preparation for the launch of the James Webb Space Telescope (JWST). JWST will be able to directly detect exoplanetary atmospheres. The models developed and methods pioneered by this work will point the way to understanding the atmospheres of extrasolar planets. The broader impacts of this work will include the support for the summer research of six undergraduate students, including one student from UT Austin?s TAURUS program. The work will also form the basis of a PhD thesis. The proposed work will use new models of brown dwarf atmospheres to understand high-resolution spectra for approximately 50 brown dwarfs from the Brown Dwarf Spectroscopic Survey and from the IGRINS instrument, and up to 2000 or more low-resolution spectra from the SpeX Prism Spectral Library. The atmosphere models will be developed from the existing Sonora model grid. The team will develop a new open-source module for ultracool brown dwarfs for the Starfish spectroscopic inference tool. The new module, combined with improved line lists for spectroscopic fitting and refined methodologies, will give the community a new resource for understanding brown dwarf and exoplanetary atmospheres. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.