NSTARS: Understanding the L- and T-dwarfs

New Mexico State University, Las Cruces NM

Investigators

Abstract

AST-0086288 Marley, Mark "NStars: Understanding the L-dwarfs and T-dwarfs" Dr. Marley is working to produce a model spectral catalog for L-dwarf and T-dwarf stars. Also known as 'brown dwarf stars,' most of these objects are below the hydrogen-burning limit for normal stars. To facilitate the discovery of and subsequent follow-up research on brown dwarfs Dr. Marley and colleagues are computing a library of theoretical high-resolution spectra covering the wavelength regime of 0.5-1000 micrometers appropriate for objects with effective temperatures ranging from 500-2200 K and metallicities ranging from -2 < [Fe/H] < 0.5. The models include the opacity of alkali metals and the influence of dusty condensates. The resulting model spectra are compared to the observed spectra of L- and T-dwarfs over the full temperature and age ranges of L- and T-dwarfs. The results are distributed to the scientific community via the web. Funding for this project was provided by the NSF Stellar Astronomy & Astrophysics (AST/SAA) program through the joint NSF/NASA "Nearby Stars (NStars)" initiative, and the NSF Mathematical & Physical Sciences Directorate Office of Multidisciplinary Activities (MPS/OMA).