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Dome A radio telescope
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Finance sought for radio telescope in Antarctica

Chinese astronomers are applying for government funding to begin construction of a radio telescope in Antarctica that could help solve the mysteries behind stars and galaxies.
The proposed facility, to be built on a giant ice cap known as Dome A, has been designed to observe terahertz, a band of electromagnetic waves normally too weak for ground-based stations to receive.

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Title: Terahertz and Far-Infrared Windows Opened at Dome A, Antarctica
Author: Sheng-Cai Shi, Scott Paine, Qi-Jun Yao, Zhen-Hui Lin, Xin-Xing Li, Wen-Ying Duan, Hiroshi Matsuo, Qizhou Zhang, Ji Yang, M.C.B. Ashley, Zhaohui Shang, Zhong-Wen Hu

The terahertz and far-infrared (FIR) band, from approximately 0.3 THz to 15 THz (1 mm to 20 micron), is important for astrophysics as the thermal radiation of much of the universe peaks at these wavelengths and many spectral lines that trace the cycle of interstellar matter also lie within this band. However, water vapour renders the terrestrial atmosphere opaque to this frequency band over nearly all of the Earth's surface. Early radiometric measurements below 1 THz at Dome A, the highest point of the cold and dry Antarctic ice sheet, suggest that it may offer the best possible access for ground-based astronomical observations in the terahertz and FIR band. To address uncertainty in radiative transfer modelling, we carried out measurements of atmospheric radiation from Dome A spanning the entire water vapour pure rotation band from 20 micron to 350 micron wavelength by a Fourier transform spectrometer. Our measurements expose atmospheric windows having significant transmission throughout this band. Furthermore, by combining our broadband spectra with auxiliary data on the atmospheric state over Dome A, we set new constraints on the spectral absorption of water vapour at upper tropospheric temperatures important for accurately modelling the terrestrial climate. In particular, we find that current spectral models significantly underestimate the H2O continuum absorption.

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Title: The sky brightness and transparency in i-band at Dome A, Antarctica
Authors: 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
(Version v2)

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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