Variable stars in M37

Abstract

The CCD photometric observations of open star cluster M37 (NGC 2099) were carried out up to a limiting magnitude of V ~ 20 in both B and V filters to search for variable stars using a 2k × 4k CCD and the 1.3 m telescope at the Vainu Bapu Observatory, Kavalur. A total of 314 stars were in the first observing run, out of which 60 were identified as variables. Eight out of the identified 60 variables are classified as W UMa binary stars. For model fitting, we used PHOEBE based on the W-D code to estimate the physical parameters of these newly detected W UMa binaries that theoretically best match the observed light curves.