PI: Daniel Jaffe, University of Texas, Austin, email@example.com
Address: Astronomy Department, C1400 RLM 15.310, Austin, TX 78712, USA
CoI: Katelyn Allers, University of Texas, Austin
CoI: Greg Doppmann, Gemini Observatory
Title: A Spectroscopic Study of Young 5-100 M_\rm J Objects in Lupus and Cham II
Abstract: By studying brown dwarfs when they are young and bright, we can investigate the nature of objects with extremely low masses and test our understanding of star formation and protostellar evolution at one extreme of the mass range. We have used very deep IJHK imaging combined with Spitzer 3.5-24 (micron) observations to identify a sample of young brown dwarfs in nearby star forming regions. The presence of circum- object disks confirms the youth of these sources and their association with the parent clouds. The objects have luminosities from 10^-4 to 10^-1 L_\odot with a substantial fraction at or below the lowest luminosities previously reported for young brown dwarfs. For ages of 1- 3\times 10^6 years, the lowest mass objects are ~2M_J and half are below the deuterium burning limit. We will use GNIRS to take R=1700 JHK spectra of a subsample of these young brown dwarfs. We will use the spectroscopic results to produce a low-gravity sequence for L-type objects. We will test models of young BD atmospheres in a regime where uncertain molecular opacities and the effects of dust settling have not been confronted with observations. We will use the spectroscopic and photometric data for the whole sample to place these young brown dwarfs in an HR diagram to investigate the evolutionary state of the extended low mass population in star forming clouds.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360