SIMBAD references

Here we consider the presence of absorption components shifted to the violet or red side of the main spectral line (satellite or discrete absorption components, i.e., SACs or DACs) in the regions of the Mg II resonance lines in Be stars as well as their kinematical characteristics. Namely, our objective is to check whether there exists a common physical structure for the atmospheric regions creating SACs or DACs of the Mg II resonance lines. In order to do this, a statistical study of the Mg II λλ 2795.523, 2802.698 A lines in the spectra of 64 Be stars of all spectral subtypes and luminosity classes was performed. We found that the atmospherical absorption regions where the Mg II resonance lines originated may be formed of several independent density layers of matter that rotate with different velocities. It was also attempted to separate SACs and DACs according to low or high radial velocity. The emission lines were detected only in the earliest and latest spectral subtypes.