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DIRECT Distances to Nearby Galaxies Using Detached Eclipsing Binaries and Cepheids. VI. Variables in the Central Part of M33

L. M. Macri·K. Z. Stanek·D. D. Sasselov·M. Krockenberger·J. Kaluzny
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Abstract

The DIRECT project aims to determine direct distances to two important galaxies in the cosmological distance ladder - M31 and M33 - using detached eclipsing binaries (DEBs) and Cepheids. We present the results of the first large-scale CCD-based search for variables in M33. We have observed two fields located in the central region of M33 for a total of 95 nights on the F. L. Whipple Observatory 1.2-m telescope and 36 nights on the Michigan-Dartmouth-MIT 1.3-m telescope. We have found a total of 544 variables, including 251 Cepheids and 47 eclipsing binaries. The catalog of variables is available online, along with finding charts and BVI light curve data (consisting of 8.2x10^4 individual measurements). The complete set of CCD frames is available upon request.

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L. M. Macri, K. Z. Stanek, D. D. Sasselov, M. Krockenberger, J. Kaluzny. 2001-02-07. DIRECT Distances to Nearby Galaxies Using Detached Eclipsing Binaries and Cepheids. VI. Variables in the Central Part of M33. https://doi.org/10.1086/318773

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