Variable stars in Southern polar region

The multi-year photometric stability is better than 1% for bright stars in uncrowded regions, with a 3{sigma} limiting magnitude of g=16 in dark time. In this study, covering all stars 9<m_v_<14.5, in declinations -75{deg} to -90{deg}, and searching for high-amplitude variability, we recover 346 known variables and discover 303 new variables, including 168 eclipsing binaries. We characterize the discoveries and provide the amplitudes, periods, and variability type.

A 1.7R_J_ planet candidate with a late K-dwarf primary was found and the transit signal was verified with the PROMPT telescope network. Further follow-up revealed this object to be a likely grazing eclipsing binary system with nearly identical primary and secondary K5 stars. Radial-velocity measurements from the Goodman Spectrograph on the 4.1 meter SOAR telescope of the likely lowest-mass targets reveal that six of the eclipsing binary discoveries are low-mass (0.06-0.37M_{sun}_) secondaries with K-dwarf primaries, strong candidates for precision mass-radius measurements.