Discovery of Three Period-bouncer Candidates from TESS Data

Period bouncers, highly evolved cataclysmic variables (CVs), are predicted to make up 40%–70% of the Galactic CV population, but only a few such systems are currently known. Searching for more samples is important to understand the evolutionary stage of CVs. We found three candidate period bouncers from Transiting Exoplanet Survey Satellite (TESS) data through Stage A superhump analysis. Stages A, B, and C of superhumps in the superoutbursts were determined by the O − C method. The stage A superhump method was used to estimate the mass ratio q of SU UMa stars. The evolutionary stage of dwarf novae was inferred from the relationship between the orbital period and mass ratio. A total of three SU UMa–type stars were found to be period-bouncer candidates with this method. Among them, 1RXS J185310.0+594509 and RZ LMi may be near the period minimum. We determine the mean superhump periods and their associated precession cycles for the targets, whose precession cycles lie in the range 2.39–2.83 days.