Period changes and the distortion of the light curve of the eclipsing variable CQ Cep with a WR component

The changes in the period of the eclipsing binary CQ Cep, one component of which is a WR-type star are analysed using new photo-electric observations. The shortening of the period stopped at approximately J.D. 2 430 000. The effect of the light curve distortion on the determination of the time of the minimum and on the behaviour of O - C deviations is discussed. The changes in the period are explained in terms of the mass-loss mechanism and mass transfer between the components of the binary. (author)