Parallax and Distance Estimates for Twelve Cataclysmic Variable Stars

We report parallax and distance estimates for 12 more cataclysmic binaries and related objects observed with the 2.4 m Hiltner telescope at MDM Observatory. The final parallax accuracy is typically ~1 mas. Notable results include distances for V396 Hya (CE 315), a helium double degenerate with a relatively long orbital period, and for MQ Dra (SDSSJ155331+551615), a magnetic system with a very low accretion rate. We find that the Z Cam star KT Persei is physically paired with a K main-sequence star lying 15 arcsec away. Several of the targets have distance estimates in the literature that are based on the white dwarf's effective temperature and flux; our measurements broadly corroborate these estimates, but tend to put the stars a bit closer, indicating that the white dwarfs may have larger masses than assumed. As a side note, we briefly describe radial velocity spectroscopy that refines the orbital period of V396 Hya to 65.07 ± 0.08 minutes.

Based on observations obtained at the MDM Observatory, operated by Dartmouth College, Columbia University, Ohio State University, the University of Michigan, and Ohio University.