Presentation #204.03 in the session Pulsating Variable Stars — iPoster Session.
RV Tauri Variable stars are pulsating evolved stars identified by a characteristic feature in their light curves: alternating deep and shallow minima. Many of the RV Tau stars were originally classified decades ago using visual observations and photographic plates. Recent scrutiny of RV Tau stars suggests there are imposters, or misclassified variables, amongst the catalog. Our aim was to improve the classification and identification of RV Tau stars and remove the imposters. We used the General Catalog of Variable Stars (GCVS) to identify “known” and “suspected” RV Tau variable stars. Next we cross-correlated these samples with the observations taken by the All Sky Automated Survey for Supernova (ASAS-SN). The resulting ASAS-SN light curves of the 84 “known” and “suspected” RV Tau stars cover a time period of at least 2 years with an average of approximately 200 photometry measurements in the V filter for each star. The light curves range from the 16th to 9th magnitude, with a median value of the 12th magnitude. For each light curve we considered the period reported by the GCVS, the Fourier transform period determined by ASAS-SN, and our own period estimate, which was determined from Lomb-Scargle periodograms. The phase-folded light curves were used to identify the period that best demonstrates the RV Tau alternating minima phenomenon. We found that alternating minima often leads to confusion for automatic classification of the variability type. Our results include updated classifications, a list of potential imposters, and the optimized periods for the stars in our study.
This material is based upon work supported by the National Science Foundation under Grant No. 1745460.