Minute-cadence observations on Galactic plane with Wide Field Survey Telescope (WFST): Overview, methodology and early results

Jie Lin; Tinggui Wang; Minxuan Cai; Zhen Wan; Xuzhi Li; Lulu Fan; Qingfeng Zhu; Ji-an Jiang; Ning Jiang; Xu Kong; Zheyu Lin; Jiazheng Zhu; Zhengyan Liu; Jie Gao; Bin Li; Feng Li; Ming Liang; Hao Liu; Wei Liu; Wentao Luo; Jinlong Tang; Hairen Wang; Jian Wang; Yongquan Xue; Dazhi Yao; Hongfei Zhang; Xiaoling Zhang; Wen Zhao; Xianzhong Zheng

arXiv · 2412.12601

Minute-cadence observations on Galactic plane with Wide Field Survey Telescope (WFST): Overview, methodology and early results

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Abstract

As the time-domain survey telescope of the highest survey power in the northern hemisphere currently, Wide Field Survey Telescope (WFST) is scheduled to hourly/daily/semi-weekly scan northern sky up to ~23 mag in four optical (ugri) bands. Unlike the observation cadences in the forthcoming regular survey missions, WFST performed "staring" observations toward Galactic plane in a cadence of $\approx$1 minute for a total on-source time of about 13 hours, during the commissioning and pilot observation phases. Such an observation cadence is well applied in producing densely sampling light curves and hunting for stars exhibiting fast stellar variabilities. Here we introduce the primary methodologies in detecting variability, periodicity, and stellar flares among a half million sources from the minute-cadence observations, and present the WFST g-/r-band light curves generated from periodic variable stars and flaring stars. Benefit from high photometric precisions and deep detection limits of WFST, the observations have captured several rare variable stars, such as a variable hot white dwarf (WD) and an ellipsoidal WD binary candidate. By surveying the almost unexplored parameter spaces for variables, WFST will lead to new opportunities in discovering unique variable stars in the northern sky.

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Jie Lin, Tinggui Wang, Minxuan Cai, Zhen Wan, Xuzhi Li, Lulu Fan, Qingfeng Zhu, Ji-an Jiang, Ning Jiang, Xu Kong, Zheyu Lin, Jiazheng Zhu, Zhengyan Liu, Jie Gao, Bin Li, Feng Li, Ming Liang, Hao Liu, Wei Liu, Wentao Luo, Jinlong Tang, Hairen Wang, Jian Wang, Yongquan Xue, Dazhi Yao, Hongfei Zhang, Xiaoling Zhang, Wen Zhao, Xianzhong Zheng. 2024-12-17. Minute-cadence observations on Galactic plane with Wide Field Survey Telescope (WFST): Overview, methodology and early results. https://arxiv.org/abs/2412.12601

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