ROTATIONAL VELOCITIES OF THE COMPONENTS OF 23 BINARIES

Abstract

By using high dispersion spectra obtained by the 1.8 m telescope of Bohyunsan Optical Astronomy Observatory (South Korea), multiline least-square deconvolution of line profiles, and Fourier analysis techniques, we obtained the rotational velocities of the components of 23 binary systems. The rotational velocities for nine primary, eight secondary, and one tertiary components of these systems were determined for the first time. The rotational velocities for primary components of seven systems appeared to be significantly different than the corresponding synchronous values (more than twice as fast for five systems, and less than half as fast for two systems). Our velocities for AU Mon, RY Gem, and RZ Eri are significantly lower than the previously published values obtained by using one or very few lines. We show that these discrepancies can be explained by strong blending of the lines in the spectra of the primaries with strong lines of the secondaries, by influence of gaseous streams, and maybe by nonsolar chemical compositions.