Photometric Studies of the Near‐Contact Binary AX Draconis

Abstract

ABSTRACTWe have obtained CCD photometric observations of the near‐contact binary AX Dra during two observing seasons from 2001 March through May and from 2003 April and May. From these measurements, the seasonal light curves of AX Dra for 2001 and 2003 were compiled, and a total of 13 new timings of minimum light were calculated. An analysis of the resulting O - C diagram reveals evidence for a periodic change with a semiamplitude of 0.0061 days and a period of 56.1 yr, but this conclusion depends entirely on the photographic plate estimates around 1960. Our light curves display the conventional O’Connell effect and small‐scale year‐to‐year light variability. If these light variations are produced by a stellar spot, a cool‐model spot on the secondary star satisfies both seasonal light curves quite well. The same representation applies to the only other published photoelectric light curves.