FAINT M-DWARF AND THE STRUCTURE OF THE GALACTIC DISK

We use broadband photometry and low-resolution spectra of a complete s ample of late-type K and M dwarfs brighter than I=22 in three fields a t high galactic latitude to study issues relating to galactic structur e and large-scale abundance gradients in the Galaxy. The observed star counts in each field are a good match to the predictions of models bas ed on deep starcount data in other intermediate-latitude fields, and t hese models identify the late-type stars as members of the Galactic di sk. Abundances for these late-type stars are estimated via narrow-band indices that measure the strength of the TiO and CaH bands in their s pectra. Our results show that the average abundance in the Galactic di sk remains close to solar even at heights of more than 2 kpc above the Plane.