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DIRECT Distances to Nearby Galaxies Using Detached Eclipsing Binaries and Cepheids. IX. Variables in the Field M31Y Discovered with Image Subtraction

A. Z. Bonanos·K. Z. Stanek·D. D. Sasselov·B. J. Mochejska·L. M. Macri·J. Kaluzny
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Abstract

The DIRECT Project aims to obtain direct distances to two Local Group galaxies, M31 and M33, which occupy a crucial position near the bottom of the cosmological distance ladder. The first step is to search for detached eclipsing binaries (DEBs) and Cepheids using 1 m class telescopes to select good candidates, which will be followed up spectroscopically on 6.5-10 m class telescopes. In this ninth paper we present a catalog of variable stars discovered with image subtraction in field M31Y [RA=10.97 deg, Dec=41.69 deg, J2000.0]. The data were obtained with the FLWO 1.2 m telescope on 25 nights, over a period of 6 months. In our search covering 22x22 arcmin we discovered 41 eclipsing binaries, 126 Cepheids, and 97 other periodic or nonperiodic variables, including a LBV candidate, a nova and a galactic CV. The catalog of variables, as well as their photometry and finding charts, is available electronically via anonymous ftp and the World Wide Web. The complete set of the CCD frames is available upon request.

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A. Z. Bonanos, K. Z. Stanek, D. D. Sasselov, B. J. Mochejska, L. M. Macri, J. Kaluzny. 2003-04-09. DIRECT Distances to Nearby Galaxies Using Detached Eclipsing Binaries and Cepheids. IX. Variables in the Field M31Y Discovered with Image Subtraction. https://doi.org/10.1086/375762

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