Search for variable stars in the open cluster NGC 2509

Abstract

This work presents the first photometric variability survey of the open cluster NGC 2509 carried out in February, 2017. Data of four nights was analysed by ensemble photometry technique, using 1k × 1k CCD and 1.3 m telescope in V and B filters. The observations were carried out upto limiting magnitude (v∼20) in both V and B filters to search for variable stars. From the phase plots using periods obtained from Schuster and Lomb Scargle periodogram, 16 objects were classified as suspected variables owing to their low amplitude variations in phase. For the remaining objects in the cluster, it is hard to establish their variability.