High-velocity winds in close binaries with accretion disks. II. The view along the plane of the disk.

Abstract

The authors present phase-resolved, ultraviolet spectra of the eclipsing cataclysmic binaries RW Trianguli and DQ Herculis. Both stars display N V λ1240, Si IV λ1400, C IV λ1549, and He II λ1640 in emission. The strongest spectral feature in both stars is C IV λ1549. In RW Tri the blue wing of this line extends to velocities of -3000 km s^-1. In both stars there is a deep eclipse of the UV continuum, representing an occultation of the interior regions of an accretion disk surrounding the degenerate dwarf. None of the spectral lines in either binary system are eclipsed to the same degree as the UV continuum, indicating that the lines are formed in an extended region above and below the disk. The distinctive morphology of RW Tri's lines suggests an origin in an accelerating wind.