PERIODICAL VARIATIONS OF RADIAL VELOCITIES AND PROFILES OF THE SODIUM LINES IN THE SPECTRUM OF THE SUPERGIANT 89 HER (F2 IBE)

Abstract

The variations in the spectral parameters of the sodium doublet Na I D line of the high latitude supergiant 89 Her were investigated on the basis of the spectrograms obtained at the 2-m telescope of Shamakhy Astrophysical Observatory for 1975-2017. It has been found that the sodium doublet Na I D line's radial velocity of the absorption component varies with a period of 5000 days. The orbital elements of the binary system were determined for the first time within the spectral-binary system model.