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CCD Photometry of Faint Variable Stars in the Globular Cluster NGC 6752

Ian B. Thompson·Janusz Kaluzny·Wojtek Pych·Wojtek Krzeminski
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Abstract

We present the results of a photometric survey for variable stars in the field of the nearby globular cluster NGC 6752. The cluster was monitored in 1996 and 1997 for a total of 54 hours with 3 different CCD cameras mounted on the 1.0-m Swope telescope. Eleven new variables were identified: 3 SX Phe stars, 7 contact binaries and 1 candidate detached eclipsing binary. All 3 SX Phe variables are likely members of the cluster while only 1 out of the 7 contact binaries is a potential cluster member. As a by-product of our survey we obtained UBV photometry for a large sample of stars in the cluster field. Two stars with U-B \approx -1.0 and V=19.3 and V=20.6 were identified. They lie along the extended horizontal branch of the cluster, and are likely to be faint sdB stars from NGC 6752.

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Ian B. Thompson, Janusz Kaluzny, Wojtek Pych, Wojtek Krzeminski. 1999-04-02. CCD Photometry of Faint Variable Stars in the Globular Cluster NGC 6752. https://doi.org/10.1086/300918

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