Proper Motions of Faint Ultraviolet-bright Sources in the Sandage Two-Color Survey of the Galactic Plane

Abstract

Proper motions with values >=10 or <=-10 mas yr^-1 have been extracted from the USNO-B1.0 and Tycho-2 catalogs for all Lanning UV-bright sources identified in the Sandage Two-Color Survey of the Galactic Plane and presented in Papers I-VI. Of the 572 sources examined, we find at least 213 that exhibit a significantly large proper motion. Based on the location of the sources in a reduced proper motion diagram, we demonstrate that about two-thirds of the high proper motion sources are likely or very likely to be heretofore unidentified white dwarfs.