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In 2008 January the 24th Chinese expedition team successfully deployed the Chinese Small Telescope ARray (CSTAR) to Dome A, the highest point on the Antarctic plateau. CSTAR consists of four 14.5cm optical telescopes, each with a different filter (g, r, i and open) and has a 4.5°×4.5° field of view (FOV). Based on the CSTAR data, initial statistics of astronomical observational site quality and light curves of variable objects were obtained. To reach higher photometric quality, we are continuing to work to overcome the effects of uneven cirrus cloud cirrus, optical “ghosts” and intra-pixel sensitivity. The snow surface stability is also tested for further astronomical observational instrument and for glaciology studies.
We have selected a PPN candidates sample from IRAS color-color diagram. The selected criteria, the objects list of whole sample and photometric and spectroscopic observational results for southern objects have been published (paper I, Hu et al, 1993), and CO and OH maser observations for the total sample are published in 1994 (paper II, Hu et al, 1994). The 20 northern objects were observed. The optical photometric observations were taken at the J. Kapteyn telescope with CCD camera, infrared photometric observations were obtained with 1.26 meter infrared telescope at Xinglong station, Beijing Observatory, and spectroscopic observational observations were carried out using the FOS attached on the 2.5 meter Issac Newton telescope in 1989; in 1996 and 2001 we re-observed these objects using 2.16 m telescope and OMR spectroscopy at Xinglong station, Beijing Observatory. We have not found any variations between two epochs for most objects in their optical spectra except IRAS 19367+2458. The spectra we obtained in 1989 IRAS 19367+2458 is a planetary nebula with [WC] core star (Hu and Dong, 1992), but in our spectra obtained in 1996 and 2001 it is a M-type star. There are two possibilities: 1. We made mistakes of identification, if so, where is the planetary nebula? 2. It varies, but we can not find any difference in the spectra obtained in 1996 and 2001. The question is still open, more observations are needed in the future.
Hu et al (1993) have selected a sample of proto-planetary nebula candidates based on the IRAS color-color diagram. IRAS 01005+7910 is one object of this sample. We have observed this object photometrically (Table 1) and spectroscopically (Fig. 1). From its spectral type of B2I and optical color of B - V = 0.23, we can derive the reddening as E(B - V) = 0.39 and interstellar/circumstellar absorption Av = 1.20. If it is a normal B-type supergiant, the distance module will be m - M = 16.05 and distance d = 16.2 kpc. Due to the galactic latitude b = 16.6, it should be located at about 4.6 kpcabove the galactic plane. This does not fit with normal B-type supergiant and we considered that it is a post-AGB star located at high galactic latitude. Recently Hrivnak et al (2000) found that this object shows carbon-rich features in the infrared. A paper on observations, reduction and discussions of this object has been submitted to the Chinese Journal of Astronomy and Astrophysics.
We present here the Beijing Astronomical Observatory Supernova Survey (BAOSS). The motivation and the strategy of the survey are briefly discussed, and the hardware and the software of the system are described. BAOSS started in 1996 and has discovered 40 supernovae (SNe) in four years, thus playing an important role in the search for nearby supernovae. The results of several well-observed SNe discovered by BAOSS, SNe 1996W, 1996cb, 1997br, and 1998S, are reported.
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