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arXiv · 1001.4951

The sky brightness and transparency in i-band at Dome A, Antarctica

Hu Zou·Xu Zhou·Zhaoji Jiang·M. C. B. Ashley·Xiangqun Cui·Longlong Feng·Xuefei Gong·Jingyao Hu·C. A. Kulesa·J. S. Lawrence·Genrong Liu·D. M. Luong-Van·Jun Ma·A. M. Moore·Weijia Qin·Zhaohui Shang·J. W. V. Storey·Bo Sun·T. Travouillon·C. K. Walker·Jiali Wang·Lifan Wang·Jianghua Wu·Zhenyu Wu·Lirong Xia·Jun Yan·Ji Yang·Huigen Yang·Yongqiang Yao·Xiangyan Yuan·D. York·Zhanhai Zhang·Zhenxi Zhu
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Abstract

The i-band observing conditions at Dome A on the Antarctic plateau have been investigated using data acquired during 2008 with the Chinese Small Telescope ARray. The sky brightness, variations in atmospheric transparency, cloud cover, and the presence of aurorae are obtained from these images. The median sky brightness of moonless clear nights is 20.5 mag arcsec^{-2} in the SDSS $i$ band at the South Celestial Pole (which includes a contribution of about 0.06 mag from diffuse Galactic light). The median over all Moon phases in the Antarctic winter is about 19.8 mag arcsec^{-2}. There were no thick clouds in 2008. We model contributions of the Sun and the Moon to the sky background to obtain the relationship between the sky brightness and transparency. Aurorae are identified by comparing the observed sky brightness to the sky brightness expected from this model. About 2% of the images are affected by relatively strong aurorae.

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Hu Zou, Xu Zhou, Zhaoji Jiang, M. C. B. Ashley, Xiangqun Cui, Longlong Feng, Xuefei Gong, Jingyao Hu, C. A. Kulesa, J. S. Lawrence, Genrong Liu, D. M. Luong-Van, Jun Ma, A. M. Moore, Weijia Qin, Zhaohui Shang, J. W. V. Storey, Bo Sun, T. Travouillon, C. K. Walker, Jiali Wang, Lifan Wang, Jianghua Wu, Zhenyu Wu, Lirong Xia, Jun Yan, Ji Yang, Huigen Yang, Yongqiang Yao, Xiangyan Yuan, D. York, Zhanhai Zhang, Zhenxi Zhu. 2011-01-07. The sky brightness and transparency in i-band at Dome A, Antarctica. https://doi.org/10.1088/0004-6256%2F140%2F6%2F2146

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