RZ SGE : a new SU UMa type dwarf nova.

The dwarf nova RZ Sagittae was found to be undergoing a supermaximum in 1981 October, making it a new member of the SU Ursae Majoris class of cataclysmic variables (and only the fourth known in the Northern Hemisphere). On four consecutive nights of high-speed photometry obtained during this supermaximum, RZ Sge exhibited recurrent 0.2 mag 'superhumps' with a period that decreased from 101.3 to 100.8 minutes. The long-term behavior of RZ Sge, as recorded by amateur variable-star observers, reveals supermaxima lasting about 11 days at a mean interval of 266 days, as well as numerous normal short maxima lasting 2-3 days.