High quality IUE spectra of AG Dra gathered during 1979-81 were examined in concert with data taken at VILSPA. Visual bursts were detected in 1980 and 1983 and were associated with order of magnitude changes in the UV continuum and emission lines. Variability was persistent in the UV and He II lines after the bursts while the C IV line displayed small variations and the N V line was nearly constant. A binary system is indicated, composed of a nonvariable K-giant and a dwarf companion which accretes matter from a cooled stellar wind. The variability would arise from an extended region near the cool star heated by UV or X ray radiation from the giant. A wider range of spectral data are required to flesh out the physical processes of the accre...
Context. AG Draconis is the brightest symbiotic star in X-rays and one of the prototypes of the supe...
The symbiotic system AG Dra regularly undergoes quiescent and active stages which consist of the ser...
We present the first X-ray observations of the 4 Draconis system, consisting of an M3III giant with ...
High quality IUE spectra of AG Dra gathered during 1979-81 were examined in concert with data taken ...
New high and low resolution IUE spectra of AG Dra, obtained when the star was still in its active ph...
The halo symbiotic star AG Dra has been monitored spectroscopically at the Tartu Observatory, Estoni...
The extensive IUE observations of the symbiotic system AG Draconis along seventeen years have allowe...
We have analyzed the complete set of available IUE (International Ultraviolet Explorer) spectra for ...
The recent 1994-1995 active phase of AG Draconis has given us for the first time the opportunity to ...
We present the results of an extensive campaign of coordinated X-ray (ROSAT) and UV (IUE) observatio...
Context. AG Dra is one of a small group of low metallicity S-type symbiotic binaries with K-type gia...
We present the results of an extensive campaign of coordinated X-ray (ROSAT) and UV (IUE) observatio...
The symbiotic system AG Dra is one of the best representatives of the category of the supersoft X-ra...
Context. AG Dra is one of a small group of low metallicity S-type symbiotic binaries with K-type gia...
We present some results of an ongoing study of the long-term spectroscopic variations of AG Dra, a p...
Context. AG Draconis is the brightest symbiotic star in X-rays and one of the prototypes of the supe...
The symbiotic system AG Dra regularly undergoes quiescent and active stages which consist of the ser...
We present the first X-ray observations of the 4 Draconis system, consisting of an M3III giant with ...
High quality IUE spectra of AG Dra gathered during 1979-81 were examined in concert with data taken ...
New high and low resolution IUE spectra of AG Dra, obtained when the star was still in its active ph...
The halo symbiotic star AG Dra has been monitored spectroscopically at the Tartu Observatory, Estoni...
The extensive IUE observations of the symbiotic system AG Draconis along seventeen years have allowe...
We have analyzed the complete set of available IUE (International Ultraviolet Explorer) spectra for ...
The recent 1994-1995 active phase of AG Draconis has given us for the first time the opportunity to ...
We present the results of an extensive campaign of coordinated X-ray (ROSAT) and UV (IUE) observatio...
Context. AG Dra is one of a small group of low metallicity S-type symbiotic binaries with K-type gia...
We present the results of an extensive campaign of coordinated X-ray (ROSAT) and UV (IUE) observatio...
The symbiotic system AG Dra is one of the best representatives of the category of the supersoft X-ra...
Context. AG Dra is one of a small group of low metallicity S-type symbiotic binaries with K-type gia...
We present some results of an ongoing study of the long-term spectroscopic variations of AG Dra, a p...
Context. AG Draconis is the brightest symbiotic star in X-rays and one of the prototypes of the supe...
The symbiotic system AG Dra regularly undergoes quiescent and active stages which consist of the ser...
We present the first X-ray observations of the 4 Draconis system, consisting of an M3III giant with ...