Program: GS-2007B-Q-219

L subdwarfs are metal-deficient, halo population counterparts to the L dwarf class, encompassing sources down to (and possibly below) the hydrogen burning minimum mass. These sources are useful laboratories for studying metallicity effects on low-temperature atmospheric processes, including condensate cloud formation, and provide critical tests for the current generation of brown dwarf spectral models. However, only four examples of this newly-uncovered population have been identified to date. We have now found a fifth L subdwarf in the 2MASS catalog which appears to be one of the latest-type, and hence lowest-mass, subdwarfs so far identified. This source is very faint, and our spectroscopic follow-up using 4-6m class telescopes have provided relatively poor quality data. We request time with Gemini/GMOS-S to obtain improved red optical spectral data for this source, which will enable us to classify it, examine spectral diagnostics of subsolar metallicity (including inhibition of condensate cloud formation), and determine its 3D space kinematics through radial velocity measurement.