SURFACE IMAGING OF ECLIPSING BINARY STARS .1. TECHNIQUES

Surface (Doppler) imaging techniques for mapping the temperature distr ibution of a single star are generalized to the case of an eclipsing s pectroscopic binary. In this paper we study three main questions, cruc ial for further application of the techniques: (a) Can we map both com ponents of a binary system simultaneously and what are the consequence s of an eclipse for the mapping? (b) What kind of mapping quality shou ld we expect in different configurations and what observational data a re required to get a reliable map? (c) What sort of distortion of the map is produced by errors in the parameters of the binary system (in p eriod, eccentricity, inclination, etc.)? We found that the method desc ribed in this paper can be successfully used for imaging eclipsing bin ary systems. The resulting map is more sensitive to the errors in the parameters of the system than is the case of a single star. Characteri stic distortions of the map can be used as indicators for fine tuning of some of the parameters. We also found that a good phase coverage of the observations is most important for reducing the artificial equato rial symmetry, typical for the line profile inversion when used for hi gh inclination binary systems.