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http://dx.doi.org/10.5303/JKAS.2016.49.3.65

NEW CCD OBSERVATIONS AND THE FIRST PHOTOMETRIC STUDY OF THE CONTACT BINARY AP UMI  

AWADALLA, N.S. (Dept. of Astronomy, Stellar Lab., National Research Institute of Astronomy and Geophysics)
HANNA, M.A. (Dept. of Astronomy, Stellar Lab., National Research Institute of Astronomy and Geophysics)
ISMAIL, M.N. (Department of Astronomy, Faculty of Sciences of El Azhar University)
HASSAN, I.A. (Department of Astronomy, Faculty of Sciences of El Azhar University)
ELKHAMISY, M.A. (Dept. of Astronomy, Stellar Lab., National Research Institute of Astronomy and Geophysics)
Publication Information
Journal of The Korean Astronomical Society / v.49, no.3, 2016 , pp. 65-71 More about this Journal
Abstract
We obtain the first complete CCD light curves (LCs) of the contact binary AP UMi in the VRI bands and analyzed them by means of the PHOEBE code. A spotted model is applied to treat the asymmetry in the LCs. The LC morphology clearly shows the O'Connell effect and the solution shows an influence of star spots on both components. Such effect of star spots is common between the RS CVn and W UMa chromospherically active stars. Based on the obtained solution of the LCs we investigate the evolutionary state of the components and conclude that the system is a pre-intermediate contact binary (f = 0.29) with mass ratio q = 0.38, and it is an A-type W UMa system where the less massive secondary component is cooler than the more massive primary one.
Keywords
stars; binaries; close; binaries; eclipsing; W UMa; stars; individual AP UMi;
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