Variable Stars in the Field of the Globular Cluster NGC 3201

Abstract

We report on the discovery and analysis of 14 short-period variable stars in the field of the southern globular cluster NGC 3201, located within roughly 2 mag on either side of the main-sequence turnoff. Eleven of these variable stars are eclipsing binaries, one is an RR Lyrae, and two are thus far unclassified systems. Among the eclipsing binary stars, nine are of the W Ursae Majoris (W UMa) type, one an Algol (EA) system, and one a detached system. Using spectroscopic follow-up observations, as well as analysis of the variables' locations in the color-magnitude diagram of the cluster, we find that only one variable star (a W UMa type blue straggler) is actually a member of NGC 3201. We present the phased photometry light curves for all the variable star systems, as well as their locations in the field of view and in the color-magnitude diagram.