Investigations of late-type giant stars from the First Byurakan Spectral Sky Survey

Abstract

We study late-type giants found in the First Byurakan Survey (FBS) data base. The third Gaia data release (Gaia EDR3) photometric and astrometric data have been used to characterize our sample of 1 100 M-type giants and 130 C-type stars found at high latitudes. Phase dependent light-curves from large sky area variability data bases such as Catalina Sky Survey (CSS) and The light curves from the Catalina Sky Survey (CSS), All-Sky Automated Survey for Supernovae (ASAS-SN) and Transiting Exoplanet Survey Satellite (TESS) databases were exploited to study their variability nature. Using TESS light curves, the variability types of some objects have been established for the first time.