Variability study of the FBS M giants

Abstract

We study in this paper variability of the late-type M giants found in the First Byurakan Survey (FBS) spectroscopic data base. We used phase dependent light - curves from large sky area variability data bases such as Catalina Sky Survey (CSS) and All-Sky Automated Survey for Supernovae (ASAS-SN). We used also the distance information derived from Gaia EDR3 to construct the Galactic distribution of the M - type giants from the second edition of the FBS Late-Type Stars catalogue including various kinds of long period variables.