ON SOME SPECTRAL FEATURES OF WW VUL IN THE EXTERME STATE OF BRIGTNESS

Abstract

By using of a homogeneous spectral material, the spectral features of the UX Ori type star WWVul in the extreme state of its brightness have been investigated. During the period of our spectral observations (2006-2010), an optical eclipse (2008-2010) of this star in the V band was occurred. A change in the character of spectral variability (along the lines: Ha, Hb, NaI D1 and
D2, HeI 5876 Å) was revealed in the spectrum of WW Vul in 2006 (before the eclipse), 2007 (beginning of the eclipses) and 2010 (after eclipse). After an optical eclipse in the spectrum of the star WW Vul in the lines Ha, Hb, Na D1 and D2, HeI 5876 Åsynchronous variation of ejection and/or outflow directions of matter were detected. Apparently, in August 2006, rotation of the accretion disk is responsible for the spectral variability, and during 2007-2010 along with the rotation of the accretion disk, an additional mechanism appears that leads to rapid changes in the physical conditions in the region of the formation of these lines. Such a mechanism can be a magnetic field in the accretion disk and/or on the surface of a star, which determines the nature of the interaction between the star and its environment.