1989 • 1989LNP...328..167K
Abstract • The data bases derived from CTI surveys yielding high-precision homogeneous multicolor photometry to faint limiting magnitudes are studied. In particular, the goal is to spectroscopically identify white dwarf and subdwarf stars to faint limiting magnitude both in the Galactic halo and in the disk. Blue candidates selected from their outlying positions in color-magnitude or color-color diagrams are visually inspected in the CTI pixel data to ensure that they are not contaminated by the halo of a nearby very bright star or merged with one or more stars. A total of 110 objects determined to be very blue are identified, and spectroscopic identifications are used to refine the loci of white dwarfs, subdwarfs, etc. in an N-dimensional color space to fainter limiting magnitudes. The motions and velocities of the white dwarfs discovered are analyzed.