The evolution of eccentricity in the eclipsing binary system AS Camelopardalis

In 2002, 2004 and 2017 we conducted high precision CCD photometry observations of the eclipsing binary system AS Cam. By analysis of the light curves from 1967 to 2017 (our data + data from the literature) we obtained photometric elements of the system and found a change in the system’s orbital eccentricity of ∆ e = 0.03 ± 0.01. This change can indicate that there is a third companion in the system in a highly inclined orbit with respect to the orbital plane of the central binary, and its gravitational influence may cause the discrepancy between observed and theoretical apsidal motion rates of AS Cam.