Program: GN-2006B-Q-76

Title:Classifying Discoveries from a Large-area Near-infrared Proper Motion Survey
PI:J.Davy Kirkpatrick
Co-I(s): Dagny Looper, Michael Liu

Abstract

Using multi-epoch 2MASS data, we have conducted the first very large area (~4700 square degrees) near-infrared proper motion survey. The most interesting discoveries are optically faint/invisible sources that could not have been detected by previous optical motion surveys. These kinematically selected objects provide a sampling of nearby, low-luminosity stars free of color selection effects, thus allowing us to check the completeness of earlier near-infrared photometric searches. Our new survey has uncovered 151 proper motion stars (pm > 0.2 arcsec/yr, J mag < 16.5) that are invisible on optical blue and red sky survey plates. Characterizing the entire sample is necessary for statistical analysis of the nature of these objects. Although we are obtaining near-infrared classification spectroscopy of most of these using IRTF/SpeX, the subject of this proposal is the subset not observable from the IRTF. As we have seen from data already acquired, we are indeed uncovering new classes of objects. Examples include the first T subdwarf, two L subdwarfs, and several young, field L dwarfs. Identifying these missed classes of objects will help us refine future photometric selections for similar sources and provide observational tests of the new generation of substellar atmospheric models.

Publications using this program's data