On Resonance-Line Profiles Predicted by Radiation-driven Disk-Wind Models

We report on resonance-line profiles predicted by radiation-driven disk-wind models that extend radially 1 order of magnitude farther out than our previous models. Our main result is that the inclusion of a disk wind at larger radii changes qualitatively and quantitatively the line profiles predicted by the models. Our new models predict line absorption that is significantly stronger than those predicted by old models. Some of the previous line profiles exhibit a double-humped structure near the line center that is now replaced by a more plausible single, blueshifted minimum. We emphasize that the improvements in the shape as well as the strength of the absorption were achieved without changing the gross properties of the wind. In particular, our new models do not predict a higher mass-loss rate than the previous models did. The main changes in the line profiles are due to the fact that the ratio between the rotational velocity and the poloidal velocity of the wind decreases downstream. The new line profiles reproduce well the line absorption of the nova-like variable IX Vel and promise to reproduce observations of other cataclysmic variables. This success of the radiation-driven disk-wind model provides an important link between outflows in OB stars and outflows in active galactic nuclei.