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arXiv · astro-ph/9601193

CCD Photometry of Variable Stars in the Field of the Globular Cluster NGC 6397

J. Kaluzny
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Abstract

The $13.6\times 13.6$ arcmin$^{2}$ field covering the central part of the globular cluster NGC~6397 was surveyed in a search for short-period variable stars. We obtained light curves for 6 close binaries, 2 SX~Phe stars and 1 RR~Lyrae variable, 7 of which are new discoveries. Both identified SX~Phe variables are likely members of the cluster. One of the identified eclipsing binaries is most probably a field star while for the remaining 5 binaries our data do not preclude cluster membership. A $V$ vs. $B-V$ color-magnitude diagram extending from the tip of the red giant branch to below the main-sequence turnoff is presented.

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J. Kaluzny. 1996-01-31. CCD Photometry of Variable Stars in the Field of the Globular Cluster NGC 6397. https://doi.org/10.1051/aas%3A1997292

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