Presentation #201.02 in the session Stars, Cool Dwarfs, Brown Dwarfs I.
New CCD, BVRI light curves of GSC 06462-00195 were obtained by R. Samec on December 12-13, 2022, January 28, and February 1-2, 2023, at Cerro Tololo InterAmerican Observatory, Chile, in remote mode on the SARA 0.6-m Cassegrainian Reflector. The system is reported as an RR Lyrae variable in SIMBAD (ATO J063.4331-28.0686). ASAS-SN classifies it as an eclipsing binary with a mean V magnitude of 11.52, an amplitude of V~0.28, a period of 0.6334857 d, and a color index J-K=0.211. The ASAS-SN light curve confirms the variable as an extreme mass ratio, eclipsing W UMa binary. Seven BVRI eclipse timings were observed with the CTIO reflector, and 9 times of low light were taken from ASAS-SN observations. From our present observations, we determined the linear ephemeris,
JD Hel Min I = 2459978.6164 ± 0.0026 + 0.6334835 ± 0.0000018×E.
The period appears to be constant over the brief 8.6-year period study. A Wilson-Devinney analysis reveals that the system is likely an A-type (more massive component is the hottest) W UMa binary with an extreme mass ratio, q = 0.0937 ± 0.0001. Its fill-out is 66 ± 2%. One hot spot was needed to model a slight light curve asymmetry. The temperature difference of the components is ~366 K. The inclination of ~82.5° results in a long time of constant light in the primary eclipse with a duration of ~109.5 minutes or 1.82 hours. More information is given in this preliminary report.