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تسجيل مستخدم جديدIdentifying Periodic Variable Stars and Eclipsing Binary Systems with Long-Term Las Cumbres Observatory Photometric Monitoring of ZTF J0139+5245
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We present the results of our search for variable stars using the long-term Las Cumbres Observatory (LCO) monitoring of white dwarf ZTF J0139+5245 with the two 1.0-m telescope nodes located at McDonald Observatory using the Sinistro imaging instrument. In this search, we find 38 variable sources, of which 27 are newly discovered or newly classified (71%) based on comparisons with previously published catalogs, thereby increasing the number of detections in the field-of-view under consideration by a factor of $approx$ 2.5. We find that the improved photometric precision per-exposure due to longer exposure time for LCO images combined with the greater time-sampling of LCO photometry enables us to increase the total number of detections in this field-of-view. Each LCO image covers a field-of-view of $26 times 26$ and observes a region close to the Galactic plane ($b = -9.4^circ$) abundant in stars with an average stellar density of $approx 8$ arcmin$^{-2}$. We perform aperture photometry and Fourier analysis on over 2000 stars across 1560 LCO images spanning 537 days to find 28 candidate BY Draconis variables, 3 candidate eclipsing binaries of type EA, and 7 candidate eclipsing binaries of type EW. In assigning preliminary classifications to our detections, we demonstrate the applicability of the Gaia color-magnitude diagram (CMD) as a powerful classification tool for variable star studies.
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