ИСТИНА

SU UMa-type dwarf novae are a subclass cataclysmic variables (CVs) with the short periods. SU UMa-stars show two types of instabilities (thermal and tidal) in the accretion disk, they are believed to cause normal outbursts and super-outbursts. During superoutburst small amplitude variations (superhumps) with the period Psh a few percent longer than the orbital period Porb are observed. These superhumps are considered to be a result of the precession of the eccentric disk deformed by the tidal instability at the 3:1 resonance. В докладе обсуждается проблема изменения периода сверхгорбов у катаклизмических переменных типа SU UMa, возникающих как результат прецессии аккреционного диска вокруг белого карлика.