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arXiv · 1701.00484

Variable Stars Observed in the Galactic Disk by AST3-1 from Dome A, Antarctica

Abstract

AST3-1 is the second-generation wide-field optical photometric telescope dedicated to time domain astronomy at Dome A, Antarctica. Here we present the results of $i$ band images survey from AST3-1 towards one Galactic disk field. Based on time-series photometry of 92,583 stars, 560 variable stars were detected with $i$ magnitude $\leq$ 16.5 mag during eight days of observations; 339 of these are previously unknown variables. We tentatively classify the 560 variables as 285 eclipsing binaries (EW, EB, EA), 27 pulsating variable stars ($δ$~Scuti, $γ$~Doradus, $δ$~Cephei variable and RR Lyrae stars) and 248 other types of variables (unclassified periodic, multi-periodic and aperiodic variable stars). Among the eclipsing binaries, 34 show O'Connell effects. One of the aperiodic variables shows a plateau light curve and another one shows a secondary maximum after peak brightness. We also detected a complex binary system with RS CVn-like light curve morphology; this object is being followed-up spectroscopically using the Gemini South telescope.

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Lingzhi Wang, Bin Ma, Gang Li, Yi Hu, Jianning Fu, Lifan Wang, Michael C. B. Ashley, Xiangqun Cui, Fujia Du, Xuefei Gong, Xiaoyan Li, Zhengyang Li, Qiang Liu, Carl R. Pennypacker, Zhaohui Shang, Xiangyan Yuan, Donald G. York, Jilin Zhou. 2017-01-02. Variable Stars Observed in the Galactic Disk by AST3-1 from Dome A, Antarctica. https://doi.org/10.3847/1538-3881%2F153%2F3%2F104

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