Abstract
We present the preliminary results from a survey of the wind interactions in O-type double-lined spectroscopic binaries. We have begun a series of investigations on the orbital phase variations in H(alpha) for nine northern systems. Excess(alpha) emission is formed by recombination in regions of relatively higher density, and can be used to model the mass distribution of the system. Enhanced density may be caused by winds colliding between the stars and creating a bow shock. Using dynamical spectra, we describe the orbital evolution of the H(alpha) variations for two of our targets exhibiting such emission.
