Name/Affiliation: Conard Dahn and Hugh Harris (U. S. Naval Observatory)
Parallaxes for Cool Subdwarfs
Parallaxes and absolute magnitudes are presented for about 18 cool, low-luminosity, metal-poor subdwarfs measured at the Naval Observatory, Flagstaff. With other subdwarfs from other sources, a census of cool subdwarfs is shown in several color-absolute-magnitude diagrams. For this paper, "cool subdwarfs" are defined as having M_V > 14.0 and evidence of a subdwarf nature (spectroscopic evidence or a tangential velocity >150 km/s). The next step in the program will be to combine the data for these stars with data for warmer counterparts to create a complete proper motion limited sample and calculate an improved halo luminosity function to supersede the version presented earlier in Dahn et al. 1995.