WIND DYNAMICS IN SMC X-1 .1. HYDRODYNAMIC SIMULATION

We present a three-dimensional hydrodynamic simulation of the disrupte d stellar wind in the high-mass X-ray binary system SMC X-1. The three dominant processes that determine the geometry of the wind in high X- ray luminosity systems such as SMC X-1 are the X-ray suppression of th e stellar wind from the X-ray irradiated face of the primary star, the focusing of the radiatively driven wind in the X-ray shadow by the ef fects of stellar rotation, and the rapid X-ray heating of gas in the v icinity of the X-ray source, including the X-ray illuminated surface o f the primary star. The resulting distribution of circumstellar gas pr ovides a successful explanation for the asymmetric, extended eclipse t ransitions and the intensity of the deep eclipse X-ray emission in SMC X-1, as well as a possible explanation for the X-ray dips seen near s uperior conjunction of the X-ray source in Cyg X-1.