Accretion disk and boundary layer models incorporating OPAL opacities

According to standard analytical models, the continuum spectrum of an accre tion disk is independent of the opacity. To test this result more generally , we have constructed vertically averaged, optically thick models for accre tion disks and boundary layers in cataclysmic variables. We compare models constructed using a constant electron scattering opacity to those computed with the OPAL tabulated Rosseland mean opacity. We verify that the continuu m spectrum emitted from the disk is independent of the opacity, and we find that the continuum spectrum emitted from the boundary layer shows a small dependence on the opacity. This results in an increase in the boundary laye r luminosity for the OPAL model of approximately a factor of 2.5. However, the central temperature and disk width are also quite different, implying t hat models with different opacities have different thermal timescales and p erhaps different oscillation properties.