Balmer line emission profiles from cataclysmic variable accretion disk chromospheres

Stark-broadened, emisson-line profiles are computed for physical conditions extant in the chromospheres of cataclysmic variable accretion disks. These calculations follow the methods of Lin, Williams, & Stover, except that our results span the lower electron number density range of 12 less than or equal to log n(e) (cm(-3)) less than or equal to 14. The rationale for high Balmer line optical depths at accretion disk faces caused by photoionization from a source in the vicinity of the white dwarf is outlined; then a series of models based on accurate absorption line coefficients is computed. Stark-broadened line widths of up to several Doppler widths are found. These pressure-broadened profiles are enough to smear the classic double-cusped line profile significantly for chromosphere temperatures of similar to 10,000 K, which are at the high end of those considered by Lin and coworkers. Emission-line profiles with greatly smoothed cusps result in all cases except in nearly edge-on systems, where the mass accretion rate drops below 10(-10) M. yr(-1) or where the accretion disk outer radii are less than 10(10.5) cm. These results are insensitive to the shape of the boundary layer energy distribution.