About EE Cep

The variability of EE Cephei (11 mag Be star) was discovered by Romano (1956) who observed its minimum in 1952 (Epoch E=0). The star’s variability was confirmed by Weber (1956) who reported magnitudes of the previous minimum in 1947 (Epoch E=-1). Basing on these two events Romano & Perissinotto (1966) suggested that EE Cephei may be an eclipsing binary. The orbital period was determined as 5.6 years. The available light curves from all 13 epochs show strong changes of the depth and the shape for particular minima (Figs. 1 & 2). Simultaneously, variations of the colors during all eclipses, remained relatively small. Mikołajewski & Graczyk (1999) first suggested that the eclipse may be caused by a dark disc with a low mass star or a close binary in its center. Differences in the light curves of EE Cep may be caused by the precession of the disc. Broad “atmospheric” wings may precede and follow the mid eclipse by 3-4 weeks (see Fig. 3 in Gałan et al. 2012 for details). Pieńkowski et al. (2020) proposed to consider also precession of the Be-type star in addition or instead of disk precession. The results of the campaign combined with the already available data will enable to verify the conception of the system with any precession.