Upgraded Photometric System of The 85-cm Telescope at Xinglong Station

Chunhai Bai; Jianning Fu; Taoran Li; Zhou Fan; Jianghua Wu; Yong Zhao; Xianqun Zeng; Wenzhao Zhang; Peng Qiu; Guojie Feng; Xiaojun Jiang

arXiv · 1804.08565

Upgraded Photometric System of The 85-cm Telescope at Xinglong Station

Chunhai Bai·Jianning Fu·Taoran Li·Zhou Fan·Jianghua Wu·Yong Zhao·Xianqun Zeng·Wenzhao Zhang·Peng Qiu·Guojie Feng·Xiaojun Jiang

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Abstract

The 85-cm telescope at the Xinglong station is a well-operated prime focus system with high science outputs. The telescope has been upgraded since 2014 with new corrector, filters and camera, which are provided by Beijing Normal University (BNU). The filter set is Johnson-Cousins UBVRI system. We report the test results of the new system including the bias, dark current, linearity, gain and readout noise of the CCD camera . Then we derive accurate instrumental calibration coefficients in UBVRI bands with Landolt standard stars in the photometric nights. Finally, we give the limiting magnitudes with various exposure time and signal-to-noise ratio for observers as references.

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Chunhai Bai, Jianning Fu, Taoran Li, Zhou Fan, Jianghua Wu, Yong Zhao, Xianqun Zeng, Wenzhao Zhang, Peng Qiu, Guojie Feng, Xiaojun Jiang. 2018-04-23. Upgraded Photometric System of The 85-cm Telescope at Xinglong Station. https://arxiv.org/abs/1804.08565

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