Abstract
We have undertaken a systematic study of the geometry, structure, and interactions of the stellar winds of massive, close binaries as evidenced by the N V, Si IV and C IV UV resonance lines in IUE spectra. Only binaries for which wind-contaminated light curves indicate conspicuous flows are analyzed. This contribution summarizes our results for HD 159176, Y Cyg, and CW Cep that have emerged from a two-step analysis: (a) A modified version of the SEI code is employed to calculate steady-state, composite-wind model line profiles for observed wind lines. The (modeled - observed) wind-line residuals contain evidence for photospheric and wind eclipses and for wind interactions. (b) These residuals are subsequently modeled by a binary wind interaction code for the purposes of disentangling the contributions from the individual interactions and for searching for colliding wind shock fronts. Iteration between these two steps ensures compatibility of the two parameter sets. As a result, the parameters describing the individual winds, density enhancements, and shocks are determined consistently.
