DOPPLER TOMOGRAPHY OF O-TYPE BINARIES - THE PHYSICAL-PROPERTIES OF 7 SYSTEMS

We have analyzed UV photospheric lines of seven O-type binaries, by me ans of cross-correlation and Doppler tomographic methods, with the goa l of estimating the physical properties of the individual stars. These systems are HD 1337 (AO Cas), HD 47129 (Plaskett's star), HD 57060 (2 9 UW CMa), HD 37043 (Iota Ori), HD 215835 (DH Cep), HD 152218, and HD 152248. Mass ratios have been obtained primarily from a cross-correlat ion technique, but also by several other techniques. The tomographic t echniques allow us to separate the spectra of the components. We then can estimate the individual spectral types and luminosity classes of t he stars (and hence T(eff) and log g, respectively), the luminosity ra tio, and projected rotational velocities. We discuss the physical prop erties of these O-type binaries. These are some of the early results o f a large scale project involving 36 O-type double-lined binary system s (from the catalog of Batten el al. 1989) which we will study using I UE and complementary ground-based data.