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Photometry and Spectroscopy of Eclipsing Binaries in omega Centauri

J. Kaluzny·I. Thompson·W. Krzeminski·A . Olech·W. Pych·B. Mochejska
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Abstract

Detached eclipsing double line spectroscopic binaries are accurate distance indicators. They can be used for the direct determination of distances to globular clusters in which such systems can be identified. The results of major photometric surveys aimed at identification of variable stars in omega Cen are summarized. Over 43 eclipsing binaries have been identified so far in the cluster field of which only 8 objects are true detached systems. Distance and age determinations are presented for the system OGLEGC-17. The apparent distance modulus is (m-M)_{V}=14.09\pm 0.04 and the age of this binary is tau=11.8\pm 0.6 Gyr.

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J. Kaluzny, I. Thompson, W. Krzeminski, A . Olech, W. Pych, B. Mochejska. 2001-11-05. Photometry and Spectroscopy of Eclipsing Binaries in omega Centauri. https://arxiv.org/abs/astro-ph/0111089

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