Speaker: D. Kovaleva (INASAN)
Title: “Visual binary stars: data to investigate the star-formation function of binaries”
Visual binary stars are a significant component of stellar population that can be observed via a number of methods giving a variety of data. The majority of wide pairs are observed as visual binaries. Visual binaries for the most numerous observational type of binaries, the number of pairs exceeds 130,000. The statistics of orbital parameters of binary stars as well as the statistics of their physical characteristics bears traces of star formation history. However statistical investigations of the binaries are complicated by the lack and incompleteness of the observational data and by a number of observational selection effects.
The exhausting list of presently known visual binary stars was compiled by cross-matching of the objects and join of data of the three largest catalogues of visual binaries. The data on parallaxes, multicolour photometry, spectral characteristics of the stars of this list taken from other catalogues allowed to compensate partly the lack of observational data for these objects. The joint data allowed to check validity of observational values, and to investigate statistics of certain orbital and physical parameters of visual binaries. The correction for incompleteness of observational data is discussed. The obtained datasets and modern distributions on binary parameters will be used to reconstruct the initial distributions and parameters of the function of star formation for binary systems.