High rotational velocity of a region around the primary of Algol.

Abstract

An analysis of the IUE spectra of Algol near λ2800 Å is performed. For this purpose the observations are compared with the calculated synthetic spectra. Significant differences are found. Near Mg II resonance lines, the observed spectra are situated below the calculated ones at the wavelength range from λ2790 Å to λ2807 Å. This local depression is interpreted as produced by the high rotational velocity of a region around the primary star, Algol A. A mass-exchange model for this semi-detached binary system is briefly discussed, and the suggestion is made that the above-mentioned region is created by a stream of gas falling on the surface of Algol A.