High-resolution Spectroscopy of Bright L and T Dwarfs
Abstract
We propose to take IRS high-resolution spectra of three of the brightest known L and T dwarfs in order to learn more about the chemical composition and atmospheric structure of these spectral classes. This program will expand the successful initial exploratory R=600 observations we carried out as an adjunct to our larger 'Dim Suns' GTO R=90 survey of M, L, and T dwarfs. We review the results of these initial exploratory observations and show how an expanded program of R=600 IRS spectroscopy can give us unique insights into the atmospheres of brown dwarfs. The abundance of ammonia, trace molecular species, the effects of non-equilibrium chemistry, and clouds can all be studied effectively with R=600 Spitzer spectroscopy. Additionally, we request low-resolution spectroscopy and IRAC photometry of the newly discovered brightest T dwarf in the Northern hemisphere, IPMS J0136+0933. We discuss how our experiences with our initial observations will lead to reduced systematic errors (particularly those due to rogue pixels and sky subtraction). This is a GTO proposal with the time to be charged to the IRS GTO time pool.
- Publication:
-
Spitzer Proposal
- Pub Date:
- May 2007
- Bibcode:
- 2007sptz.prop40076M