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The ability to gain information on the individual components of O-type binary systems has been difficult because of the severe line blending that is present in these systems. Doppler tomography is an iterative scheme that uses an ensemble of spectra, uniformly distributed in phase, along with radial velocity curves to reconstruct the individual component spectra (see Bagnuolo,Gies and Wiggs, 1992,ApJ,385,708). These individual spectra can then be analyzed. The spectral types and luminosity classes obtained will provide indicators of the temperature and gravity of the components. Also obtainable from the individual component spectra are vsini of primary and secondary, a magnitude difference estimate, and, potentially, abundance differences. The use of IUE high dispersion spectra is optimal for O-type binary systems because of the presence of many lines in the UV. The high excitation of these lines also reduces the amount of contamination from interstellar emission. Radial velocity curves, which are necessary for the tomography algorithm, are refined by cross-correlation methods using standard spectra of appropriate spectral types. We are presently embarking upon a large scale project involving 35 O-type binary systems with over 560 spectra from the IUE. This paper presents initial radial velocity and tomographic results from 6 of these systems: D H Cep, HD 93403, HD 152218, HD 152248, HD163181, and HD 165052. All are double lined spectroscopic binaries. They range from B0.5Iae to O5f in spectral class with periods of 2.1 to 15.1 days.
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