NEW SPECTRAL OBSERVATIONS OF THE INTERACTING ECLIPSING BINARY V367 CYGNI

The results of high-dispersion CCD spectral observations of the intera cting eclipsing binary V367 Cyg near the HeI 6678 Angstrom, MgII 4481 Angstrom, SiII 6347 Angstrom, and H-alpha lines are presented. Faint e mission in the HeI 6678 Angstrom line was detected. The radial velocit y derived from this emission varies with a half-amplitude of about 180 km/s, and is in antiphase with the variations of the MgII 4481 Angstr om line, which is formed in the photosphere of the primary star. It is concluded that the He I emission is formed in the accretion disc arou nd the invisible companion. A simultaneous solution for the orbital ra dial-velocity variability curves (taking into account the inclination angle of the orbit, determined previously from polarimetric observatio ns), results in estimates for the masses of the two components M-1 con gruent to 22M. and M-2 congruent to 11M.. New orbital elements for the binary are determined. Long-term variability in the radial velocity o f the system's center of mass was also discovered. The variability of the HeI 6678 Angstrom, SiII 6347 Angstrom, and H-alpha line profiles a re used to analyze the behavior of gas flows in the system. V367 Cyg a ppears to be in an initial phase of rapid mass transfer, when matter f lows from the more massive onto the less massive component.