Variable Stars in the Field of the Globular Cluster NGC 3201

Kaspar von Braun; Mario Mateo

doi:10.1086/324641

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arXiv · astro-ph/0109433

Variable Stars in the Field of the Globular Cluster NGC 3201

Kaspar von Braun·Mario Mateo

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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 two magnitudes on either side of the main-sequence turnoff. 11 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 Ursa 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 lightcurves for all the variable star systems as well as their locations in the field-of-view and in the color-magnitude diagram.

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Kaspar von Braun, Mario Mateo. 2001-09-25. Variable Stars in the Field of the Globular Cluster NGC 3201. https://doi.org/10.1086/324641

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