Faint photometric BVRc CCD sequences

Abstract

Lists of CCD photometric standard stars in the BVRc system of Johnson and Cousins are presented for two regions of importance in studies of galactic structure and kinematics: one at the North galactic pole (NGP) (bII =8 5), and a second on the galactic equator toward the anti{center (lII = 133:2, bII = 1:6). Precision of both magnitudes and colors is better than 0.05 mag down to V =1 8 :5 for the NGP sample, and to V =1 8 : 0f or the set on the galactic plane. Accuracy is also better than 0:05 mag, as shown by comparison to standard (intrinsic) color-color diagrams. These sequences should full the needs for faint refer- ence stars in the photometric calibration of old and new large-area surveys using wide-angle photographic plates. This is the case, for example, of the new multicolor sur- veys of the Palomar Observatory, which uses the Oschin Schmidt telescope, and the Second Generation Southern Sky Survey, which utilizes UK Schmidt of the Anglo Australian Observatory in Siding Spring.