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The Multi-Wavelength Quasar Survey III. Quasars in Field 836

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chinese Journal of Astronomy and Astrophysics 2007年第3期7卷 375-379页

作者： Yu Bai Yang Chen xiang-Tao He Jiang-hua Wu Qing-Kang {2. Richard F.Green Wolfgang Voges Department of Astronomy Beijing Normal University Beijing 100875 national astronomical Observatories Chinese Academy of Sciences Beijing 100012 Kitt Peak national Observatory NOAO Tucson AZ85726-6732 USA Max-Planck-Institute fuer Extraterrestrische Physik D-85740 Garching Germany

This is the third paper in a series connected with our Multiwavelength Quasar Survey. The survey is aimed to provide a quasar sample more complete than any previous survey by using a combined selection technique to reduce selection effects. We present the observational results for the X-ray candidates in field f836. We found 15 X-ray AGNs in this field of which eight are new discoveries. The X-ray data and optical spectra of these AGNs are given. We give the X-ray candidate selection criteria, which proved to be highly efficient in isolating X-ray AGNs.

关键词： galaxies active individual (field f 836) - X-rays galaxies quasars

A Positioning System based on Communication Satellites and the chinese Area Positioning System(CAPS)

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chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 611-630页

作者： Guo-xiang Ai Hu-li Shi Hai-Tao Wu Yi-{2. Yan Yu-jing Bian Yong-Hui Hu Zhi-Gang li Ji Guo Xian-De Cai national astronomical Observatories Chinese Academy of Sciences Beijing 100012 China national Time Service Center Chinese Academy of Sciences Lintong 710600 China

The chinese Area Positioning System （CAPS） is a positioning system based on satellite communication that is fundamentally different from the 3＂G＂（GPS, GLONASS and GAliLEO） systems. The latter use special-purpose navigation satellites to broadcast navigation information generated on-board to users, while the CAPS transfers ground-generated navigation information to users via the communication satellite. In order to achieve accurate Positioning, Velocity and Time （PVT）, the CAPS employs the following strategies to over- come the three main obstacles caused by using the communication satellite：（a） by real-time following-up frequency stabilization to achieve stable frequency; （b） by using a single carrier in the transponder with 36 MHz band-width to gain sufficient power; （c） by incorporating Decommissioned Geostationary Orbit communication satellite （DGEO）, barometric pressure and Inclined Geostationary Orbit communication satellite （IGSO） to achieve the 3-D posi- tioning. Furthermore, the abundant transponders available on DGEO can be used to realize the large capacity of communication as well as the integrated navigation and communication. With the communication functions incorporated, five new functions appear in the CAPS：（1） combination of navigation and communication; （2. combination of navigation and high accu- racy orbit measurement; （3） combination of navigation message and wide/local area differen- tial processing; （4） combination of the switching of satellites, frequencies and codes; and （5） combination of the navigation message and the barometric altimetry. The CAPS is thereby labelled a PVT5C system of high accuracy. In order to validate the working principle and the performance of the CAPS, a trial system was established in the course of two years at a cost of about 2. million dollars. The trial constellation consists of two GEO satellites located at E87.5° and E110.5°, two DGEOs located at E130° and E142., as well as barometric altimetry as a virtual s

关键词： astronomy application satellite navigation satellite communication astrometry astronomic technique

Testing and data reduction of the chinese Small Telescope Array(CSTAR) for Dome A,Antarctica

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Research in Astronomy and Astrophysics 2010年第3期10卷 279-290页

作者： Xu Zhou Zhen-Yu Wu Zhao-Ji Jiang xiang-Qun Cui Long-Long Feng Xue-Fei Gong jing-Yao Hu Qi-Sheng {2. Gen-Rong {2.u Jun Ma Jia-{2. Wang {2.-Fan Wang Jiang-hua Wu {2.-Rong Xia Jun Yan xiang-Yan Yuag Feng-xiang Zhai Ru Zhang Zhen-Xi Zhu national astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Nanjing Institute of astronomical Optics ＆ Technology National Astronomical Observatories Chinese Academy of Sciences Nanjing 210042 China Purple MountainObservatory Chinese Academy of Sciences Nanjing 210008 China chinese Center for Antarctic Astronomy Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The chinese Small Telescope Array （CSTAR） is the first chinese {2. instrument on the Antarctic ice cap. The low temperature and low pressure testing of the data acquisition system was carried out in a laboratory refrigerator and on the 4500 m Pamirs high plateau, respectively. The results from the final four nights of test observations demonstrated that CSTAR was ready for operation at Dome A, Antarctica. In this paper, we present a description of CSTAR and the performance derived from the test observations.

关键词： instrumentation: detectors -- techniques: photometric -- stars: variables

A method of measuring the [α/Fe] ratios from the spectra of the LAMOST survey

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Research in Astronomy and Astrophysics 2016年第7期16卷 83-96页

作者： Ji li Chen han Mao-Sheng {2. Jian-Rong Shi jing-Kun Zhao Xiao-Wei liu hua-Wei Zhang Hai-Bo Yuan Xuan Ci Xiao-Feng Zhang Yue-{2. Wang Yang huang Yong Zhang Yong-Hui Hou Yue-Fei Wang Zi-huang Cao Department of Space Science and Astronomy Hebei Normal University Shijiazhuang 050024 China Department of Astronomy Peking University Beijing 100871 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Kavli Institute for Astronomy and Astrophysics Peking University Beijing 100871 China Department of Astronomy Beijing Normal University Beijing 100875 China Nanjing Institute of astronomical Optics & Technology National Astronomical Observatories Chinese Academy of Sciences Nanjing 210042 China

The [α/Fe] ratios in stars are good tracers to probe the formation history of stellar populations and the chemical evolution of the Galaxy. The spectroscopic survey of LAMOST provides a good opportunity to determine [α/Fe] of millions of stars in the Galaxy. We present a method of measuring the [α/Fe]ratios from LAMOST spectra using the template-matching technique of the LSP3 pipeline. We use three test samples of stars selected from the ELODIE and MILES libraries, as well as the LEGUE survey to validate our method. Based on the test results, we conclude that our method is valid for measuring [α/Fe]from low-resolution spectra acquired by the LAMOST survey. Within the range of the stellar parameters Teff= [5000, 7500] K, log g = [1.0, 5.0] dex and [Fe/H]= [onsistent with values derived from high-resolution spectra,-1.5, ＋0.5] dex, our [α/Fe] measurements are c and the accuracy of our [α/Fe] measurements from LAMOST spectra is better than 0.1 dex with spectral signal-to-noise higher than 2..

关键词： Galaxy evolution stars abundances stars fundamental parameters techniques spectroscopy surveys methods data analysis

The Multi-Wavelength Quasar Survey IV. Quasars in the Leo Cluster

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chinese Journal of Astronomy and Astrophysics 2007年第4期7卷 595-600页

作者： Yang Chen Yu Bai xiang-Tao He Jiang-hua Wu {2.g Wang Qing-Kang li Yan-Chun Sun Richard F. Green Wolfgang Voges Department of Astronomy Beijing Normal University Beijing 100875 national astronomical Observatories Chinese Academy of Sciences Beijing 100012 Large Binocular Telescope Observatory NOAO Tucson AZ85721 USA Max-Planck-Institute fur Extraterrestrische Physik D-85740 Garching Germany

We aim to provide a quasar sample that is more complete than any previous surveys by using a combined selection technique to reduce the selection effects. Here we present the observational results for the X-ray candidates in the field of the Leo Cluster. We found 33 X-ray AGNs in this field of which 10 are new discoveries. The X-ray data and optical spectra of these AGNs are given. We also study the near-IR properties of the X-ray-selected AGNs by using the data from 2.ASS. Most of the AGNs in our sample span the color range 0.0〈B-J〈2.5,1.0〈 J-Ks 〈2.0 and 0.5〈H-Ks〈1.2.

关键词： galaxies: active: individual (Leo Cluster) - X-rays: galaxies: quasars

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

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Research in Astronomy and Astrophysics 2012年第9期12卷 1197-1242页

作者： xiang-Qun Cui Yong-Heng Zhao Yao-Quan Chu Guo-Ping li Qi li li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong liu Hao-Tong Zhang De-hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-hua Jiang xiang Jiang Zi-Bo Jiang Ge jin Ai-hua li Yan li Ye-Ping li Guan-Qunliu Zhi-Gang liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao xiang-Yan Yuan Chao Zhai jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-hua Zhou Jie Zhu Si-Cheng Zou national astronomical Observatories Chinese Academy of Sciences Beijing 100012 China yzhao @ *** Nanjing Institute of astronomical Optics and Technology National Astronomical ObservatoriesChinese Academy of Sciences Nanjing 210042 China University of Science and Tecfinologyof China Hefei 230026 China Shanghai astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Architecture Design and Research Chinese Academy of Sciences Beijing 100190China

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 (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 2. 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 {2. large scientific project, the LAMOST project was formally proposed in 1996, and approved by the chinese government in 1997. The construction started in 2.01, was completed in 2.08 and passed the official acceptance in June 2.09. The LAMOST pilot survey was started in October 2.11 and the spectroscopic survey will launch in September 2.12. 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.

关键词： techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction

19 low mass hypervelocity star candidates from the first data release of the LAMOST survey

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Research in Astronomy and Astrophysics 2015年第8期15卷 1364-1377页

作者： Yin-Bi li A-li Luo Gang Zhao You-Jun Lu Peng Wei Bing Du {2. li Yong-Heng Zhao Zhan-Wen han Bo Wang Yue Wu Yong Zhang Yong-Hui Hou Yue-Fei Wang Ming Yang Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China State Key Laboratory of High-end Server & Storage Technology Jinan 250510 China Key Laboratory for the Structure and Evolution of Celestial Objects Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Nanjing Institute of astronomical Optics & Technology National Astronomical Observatories Chinese Academy of Sciences Nanjing 210042 China

Hypervelocity stars are believed to be ejected out from the Galactic center through dynamical interactions between（binary） stars and the central supermassive black hole（s）. In this paper, we report 19 low mass F/G/K type hypervelocity star candidates from over one million stars found in the first data release of the LAMOST regular survey. We determine the unbound probability for each candidate using a MonteCarlo simulation by assuming a non-Gaussian proper-motion error distribution, and Gaussian heliocentric distance and radial velocity error distributions. The simulation results show that all the candidates have unbound possibilities over 50% as expected,and one of them may even exceed escape velocity with over 90% probability. In addition, we compare the metallicities of our candidates with the metallicity distribution functions of the Galactic bulge, disk, halo and globular clusters, and conclude that the Galactic bulge or disk is likely the birth place for our candidates.

关键词： stars: low-mass—stars: kinematics and dynamics—Galaxy: abundances—stars: fundamental parameters—stars: distances

Data processing and data products from 2.17 to 2.19 campaign of astronomical site testing at Ali,Daocheng and Muztagh-ata

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Research in Astronomy and Astrophysics 2020年第6期20卷 109-130页

作者： Zi-huang Cao jin-Xin Hao Lu Feng Hugh RAJones Jian {2. jing Xu {2.-Yong {2.u Teng-Fei Song Jian-Feng Wang hua-lin Chen Yan-Jie Xue huang Shen Yong-Heng Zhao Zhao-xiang Qi Jian-Rong Shi Yuan Tian Zheng Wang Xia Wang jin-{2.ang Hou jin-Ming Bai Ji Yang Xu Zhou Yong-Qiang Yao Jia Yin A{2. Esamdin Guang-Xin Pu Peng Wei Chun-Hai Bai Guo-Jie Feng Lu Ma Xuan Zhang Yu {2.u Chong Pei Zhi-Xia Shen Yun-Ying Jiang Jian-Feng Tian Xian-Qun Zeng Zhi-Gang Hou Xu Yang Jun-Bo Zhang Shi-Long {2.ao Dong-Wei Fan Yun-Fei Xu Jian-Ping Xiong Tai-Sheng Yan Xi Zhang Chang-hua {2. Yi-han Tao Si-Cheng Yu Zhi-Song Cao Hong-Shuai Wang national astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of chinese academy of sciences Beijing 100049China Shanghai astronomical Observatory Chinese Academy of SciencesShanghai 200030China Centre for Astrophysics University of HertfordshireHatfieldUK School of Journalism Communication University of ChinaBeijing 100024China Nanjing Institute of astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China Xinjiang astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210033China beijing Kaiyang Space Technology Co. LtdBeijing 100085China

Based on previous site testing and satellite cloud data,Ali,Daocheng and Muztagh-ata have been selected as candidate sites for the Large Optical/Infrared Telescope(LOT) in *** present the data collection,processing,management and quality analysis for our site testing based on using similar *** analyze meteorological data,seeing,background light,cloud and precipitable water vapor data from 2.17 March 10 to 2.19 March *** also investigated the relative usefulness of our all-sky camera data in comparison to that from the meteorological TERRA satellite data based on a night-by-night comparison of the correlation and consistency between *** find a 6% discrepancy arising from a wide range of factors.

关键词： LOT Site-selection-data processing

Data release of the LAMOST pilot survey

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Research in Astronomy and Astrophysics 2012年第9期12卷 1243-1246页

作者： A-li Luo Hao-Tong Zhang Yong-Heng Zhao Gang Zhao {2.-Qun Cui Guo-Ping li Yao-Quan Chu Jian-Rong Shi Gang Wang Jian-Nan Zhang Zhong-Rui Bai Xiao-Yan Chen Feng-Fei Wang Yan-Xin Guo Jian-Jun Chen Bing Du Xiao Kong Ya-Juan Lei Yin-Bi li Yi-han Song Yue Wu Yan-Xia Zhang Xin-lin Zhou Fang Zuo Peng Du lin He Wen Hou Yi-Qiao Dong Jian li Guang-Wei li S{12.ng li jing Song Yuan Tian Meng-Xin Wang Yong-Hui Hou Zhi-Ying Huo Hong-Z{12.n Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-{12. Jiang {2. Jiang Zi-Bo Jiang Ge jin Ai-{12. li Qi li Yin-Dun Mao Zheng-Hong Tang Qing-Sheng Tao liang-Ping Tu Da-Qing Wang Dan Wang Jian-Ping Wang Lei Wang Shou-Guan Wang Shu-Qing Wang Ya-Nan Wang You Wang Yue-Fei Wang Ming-Zhi Wei {2.-{2. Xue Xiao-Zheng Xing ling-Zhe Xu Xin-Qi Xu Yan Xu De-{12. Yang Shi-Hai Yang Zheng-Qiu Yao Yong Yu Hui Yuan Chao Zhai En-Peng Zhang jing Zhang li-Ping Zhang WeiZhang Yong Zhang Zhen-Chao Zhang Ming Zhao Fang Zhou Yong-Tian Zhu Jie Zhu Si-Cheng Zou national astronomical Observatories Chinese Academy of Sciences Beijing 100012 China lal @ lamost o rg Nanjing Institute of astronomical Optics and Technology National Astronomical ObservatoriesChinese Academy of Sciences Nanjing 210042 China University of Science and Technologyof China Hefei 230026 China Shanghai astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Institute of Architecture Design and Research Chinese Academy of Sciences Beijing 100190China

This paper describes the data release of the LAMOST pilot survey, which includes data reduction, calibration, spectral analysis, data products and data access. The accuracy of the released data and the information about the FITS headers of spectra are also introduced. The released data set includes 319 000 spectra and a catalog of these objects.

关键词： techniques: spectroscopic survey — data reduction — data release