A model of the symbiotic star AG Dra

Spectrograms obtained at the Shemakha Astrophysical Observatory of the Azerbaidzhan Academy of Sciences has shown that AG Dra is a binary star possessing spectral lines of both components. The following parameters of the system have been determined: K/sub 1/ = 7.5 km/sec, K/sub 2/ = 21 km/sec, /gamma/ = /minus/148 km/sec. With allowance for Meinunger's orbital period of 554 days, we obtain M/sub 1/:M/sub 2/ = 2.8, M/sub 1/ sin/sup 3/ i = 0.98 M/sub /circled dot//, M/sub 2/ sin/sup 3/ i = 0.35M/sub /circled dot// and a sin i = 312R/sub /circled dot//. A model with a white dwarf that accretes stellar wind through an accretion disk is studied. The most probable model is found to be that of a gK star losing mass at 5/centered dot/10/sup /minus/8/ M/sub /circled dot///yr with a white dwarf of a mass of about 1M/sub /circled dot//. The inclination of the orbit is t /approx/ 45/degree/. Ultraviolet radiation is emitted by the disk and x rays by the surface of the white dwarf through the polar regions of the disk.