ASTRONOMY & ASTROPHYSICS, vol.363, no.1, pp.244-252, 2000 (SCI-Expanded)
New photometric data from the eclipsing binary star AI Draconis has been analyzed with the method of Wilson-Devinney. The system shows a period increase of about 0.91 sec per century, which corresponds to amass transfer from the less to the more massive component at a rate of 7.5 10(-7) M./yr under the conservative mass transfer hypothesis. We also suggest that the system has an unseen component which orbits around the mass center of the triplet system with a period of about 23 yrs. We found that the projectional angular separation between the third star and eclipsing pair varies from 0." 048 to 0." 235. These results suggestive of a third body should be checked in the future with more sensitive observations.