Multicolour photometry of the unusual cataclysmic variable AE Aquarii.

Light curves of the cataclysmic variable (CV) AE Aqr obtained in the UBV and the Walraven photometric systems are presented. Its photometric behavior on the flickering time scale is found to be significantly different from that of other CVs. AE Aqr is the only such star to exhibit extended periods devoid of flickering. During these quiet phases the light curves are characterized by ellipsoidal variations of the secondary star, the spectral type of which could be classified as K3 using spectra of the red spectral range of AE Aqr. 90-95 percent of the visual light is then emitted by the cool star, while the remaining light comes from a source with colors typical for the primary component of CVs. Three different types of flares could be identified during active phases: pure continuum flares, pure emission line flares, and mixed events. AE Aqr is concluded to show many features which are not typical for cataclysmic variables.