Lingzhe Xu

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)

The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5 ° ). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67 m×6.05 m) and active Schmidt mirror (5.74 m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.

Progress of Antarctic Schmidt Telescopes (AST3) for Dome A

Prelimenary site testing led by Chinese Center of Antarctic Astronomy (CCAA) shows that the highest point of the Antarctic Plateau Dome A has very clear sky, good seeing, slow wind, low boundary layer and very low precipitable water vapour which make it the best site on earth for optical/IR and sub-mm observations. Chinese Small Telescope ARray (CSTAR) was installed at Dome A in 2008 and have automatically observed for about 3 antarctic winters. The three Antarctic Schmidt telescopes(AST3) with entrance pupil diameter 500mm are the second antarctic project proposed by CCAA and the first AST are being constructed in NIAOT now which is planned to be mounted on Dome A at the beginning of 2011. All the tracking components were tested in the low temperature chamber and an adaptive defrosting method is designed to prevent the frost building up on the schmidt plate.

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoises reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3 single parentage assignments were determined for the population of 23 individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The Study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoises mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

Status of the first Antarctic Survey Telescopes for Dome A

The preliminary site testing carried out since the beginning of 2008 shows the Antarctic Dome A is very likely to be the best astronomical site on earth even better than Dome C and suitable for observations ranging from optical wavelength to infrared and sub-millimeter. After the Chinese Small Telescope Array (CSTAR) which is composed of four small fixed telescopes with diameter of 145mm and mounted on Dome A in 2008 for site testing and variable star monitor, three Antarctic Survey Telescopes (AST3) were proposed for observations of supernovas and extrasolar planets searching. AST3 is composed of 3 large field of view catadioptric telescopes with 500mm entrance diameter and G, R, I filter for each. The telescopes can point and track autonomously along with a light and foldable dome to keep the snow and icing build up. A precise auto-focusing mechanism is designed to make the telescope work at the right focus under large temperature difference. The control and tracking components and assembly were successfully tested at from normal temperature down to -80 Celsius degree. Testing observations of the first AST3 showed it can deliver good and uniform images over the field of 8 square degrees. The first telescope was successfully mounted on Dome A in Jan. 2012 and the automatic observations were started from Mar. 2012.

Kunlun Dark Universe Survey Telescope

Chinese Antarctic Observatory has been listed as National large research infrastructure during twelfth five-year plan. Kunlun Dark Universe Survey Telescope, one of two major facility of Chinese Antarctic Observatory, is a 2.5-meter optic/infrared telescope and will be built at the Chinese Antarctic Kunlun Station. It is intended to take advantage of the exceptional seeing conditions, as well as the low temperature reducing background for infrared observations. KDUST will adopt an innovative optical system, which can deliver very good image quality over a 2 square degree flat field of view. All of parts of it have been designed carefully to endure the extremely harsh environment. KDUST will be perched on a 14.5-meter-high tower to lift it above the turbulence layer. In this paper, preliminary design and key technology pre-research of KDUST will be introduced.

The AST3 project: Antarctic Survey Telescopes for Dome A

The AST3 project consists of three large field of view survey telescopes with 680mm primary mirror, mainly for observations of supernovas and extrasolar planets searching from Antarctic Dome A where is very likely to be the best astronomical site on earth for astronomical observations from optical wavelength to thermal infrared and beyond, according to the four years site testing works by CCAA, UNSW and PRIC. The first AST3 was mounted on Dome A in Jan. 2012 and automatically run from March to May 2012. Based on the onsite winterization performance of the first AST3, some improvements such as the usage of high resolution encoders, defrosting method, better thermal control and easier onsite assembly et al were done for the second one. The winterization observation of AST3-2 in Mohe was carried on from Nov. 2013 to Apr. 2014, where is the most northern and coldest part of China with the lowest temperature around -50°. The technical modifications and testing observation results will be given in this paper. The third AST3 will be optimized from optical to thermal infrared aiming diffraction limited imaging with K band. Thus the whole AST3 project will be a good test bench for the development of future larger aperture optical/infrared Antarctic telescopes such as the proposed 2.5m Kunlun Dark Universe Survey Telescope project.

Control system for the first three Antarctic Survey Telescopes (AST3-1)

The first Three Antarctic Survey Telescope (AST3-1), a 50/68cm Schmidt-like equatorial-mount telescope, is the first automated Chinese telescope operating on the Antarctic plateau. It is planned to be in operations at Dome A, the highest peak on the Antarctic plateau, in 2012. The telescope is unmanned during night-time operations in the Austral winter. The telescope optics and mechanics, as well as the motors and position sensors, are exposed to a very harsh environment. The mechanics is enclosed with a foldable tent-like dome to prevent snow, diamond dust and ice. While the drive boxes, most circuit, power supply and computers are located inside the warm instrumental cabin. This article describes the challenges the telescope control system encountered in night-time operations, such as the power supply limit, the harsh meteorological condition, unattended testing, automatic operation, remote control and telemetry, etc. Some solutions are also discussed in this paper, which are applied on the AST3-1 and waiting for validation. AST3-1 is also an exploration of a larger telescope on the Antarctic.

Research of remote control for Chinese Antarctica telescope based on Iridium satellite communication

Astronomers are ever dreaming of sites with best seeing on the Earth surface for celestial observation, and the Antarctica is one of a few such sites only left owing to the global air pollution. However, Antarctica region is largely unaccessible for human being due to lacking of fundamental living conditions, travel facilities and effective ways of communication. Worst of all, the popular internet source as a general way of communication scarcely exists there. Facing such a dilemma and as a solution remote control and data transmission for telescopes through iridium satellite communication has been put forward for the Chinese network Antarctic Schmidt Telescopes 3 (AST3), which is currently under all round research and development. This paper presents iridium satellite-based remote control application adapted to telescope control. The pioneer work in China involves hardware and software configuration utilizing techniques for reliable and secure communication, which is outlined in the paper too.

Progress of Antarctic survey telescopes

The Antarctic Survey Telescope-AST3 consists of three optical telescopes with 680mm primary mirror and 8 square degree field of view, mainly for observations of supernovas and extrasolar planets searching from Antarctic Dome A. The first two AST3 telescopes (AST3-1 and AST3-2) were successfully installed on Dome A by Chinese expedition team in Jan. 2012 and Jan. 2015 separately. Multi-anti-frost methods were designed for AST3-2 and the automatic observations are keeping on from March 2016. The best limited magnitude is 19.4m with exposure time 60s in G band. The third AST3 will have switchable interface for both optical camera and near infrared camera optimized for k dark band survey. Now the telescope is under development in NIAOT and the K-band camera is under development in AAO.