Curious Variables Experiment (CURVE). RZ LMi - the most active SU UMa star

Abstract

We report extensive photometry of the frequently outbursting dwarf nova RZ Leo Minoris. During two seasons of observations we detected 12 superoutbursts and 7 normal outbursts. The V magnitude of the star varied in range from 16.5 to 13.9 mag. The superoutbursts occur quite regularly flashing every 19.07(4) days and lasting slightly over 10 days. The average interval between two successive normal outbursts is 4.027(3) days. The mean superhump period observed during the superoutbursts is 0.059396(4) days (85.530(6) min). The period of the superhumps was constant except for one superoutburst when it increased with a rate of $\dot P/P_{\rm sh} = 7.6(1.9)\cdot 10^{-5}$. Our observations indicate that RZ LMi goes into long intervals of showing permanent superhumps which are observed both in superoutbursts and quiescence. This may indicate that decoupling of thermal and tidal instabilities play important role in ER UMa systems. No periodic light variations which can be connected with orbital period of the binary were seen, thus the mass ratio and evolutionary status of RZ LMi are still unknown.