%0 Journal Article
%T Close binary stars in the solar-age Galactic open cluster M67
%A K. Yakut
%A W. Zima
%A B. Kalomeni
%A H. Van Winckel
%A C. Waelkens
%A P. De Cat
%A E. Bauwens
%A M. Vuckovic
%A S. Saesen
%A L. Le Guillou
%A M. Parmaksizoglu
%A K. Uluc
%A I. Khamitov
%A G. Raskin
%A C. Aerts
%J Physics
%D 2009
%I arXiv
%R 10.1051/0004-6361/200911918
%X We present multi-colour time-series CCD photometry of the solar-age galactic open cluster M67 (NGC 2682). About 3600 frames spread over 28 nights were obtained with the 1.5 m Russian-Turkish and 1.2 m Mercator telescopes. High-precision observations of the close binary stars AH Cnc, EV Cnc, ES Cnc, the $\delta$ Scuti type systems EX Cnc and EW Cnc, and some long-period variables belonging to M67 are presented. Three full multi-colour light curves of the overcontact binary AH Cnc were obtained during three observing seasons. Likewise we gathered three light curves of EV Cnc, an EB-type binary, and two light curves of ES Cnc, a blue straggler binary. Parts of the light change of long-term variables S1024, S1040, S1045, S1063, S1242, and S1264 are obtained. Period variation analysis of AH Cnc, EV Cnc, and ES Cnc were done using all times of mid-eclipse available in the literature and those obtained in this study. In addition, we analyzed multi-colour light curves of the close binaries and also determined new frequencies for the $\delta$ Scuti systems. The physical parameters of the close binary stars were determined with simultaneous solutions of multi-colour light and radial velocity curves. Finally we determined the distance of M67 as 857(33) pc via binary star parameters, which is consistent with an independent method from earlier studies.
%U http://arxiv.org/abs/0906.4908v1