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Spectroscopic study of globular clusters in the halo of M31 with the Xinglong 2.16 m telescope

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Research in Astronomy and Astrophysics 2011年第11期11卷 1298-1310页

作者： Zhou Fan1,2.Ya-Fang Huang1,2.Jin-Zeng li1,2.Xu Zhou1,2.Jun Ma1,2.Hong Wu1,2.Tian-Meng zhang1,2.and Yong-Heng {2.1,2.1 national astronomical observatories,chinese academy of sciences,beijing 100012.china 2.Key Laboratory of Optical Astronomy,national astronomical observatories,chinese academy of sciences,beijing 100012.china national astronomical {2. Chinese Academy of Sciences Beijing 100012 China Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

We present spectroscopic observations for 11 confirmed globular clusters(GCs) of M31 with the OMR spectrograph on the 2.16 m telescope at the Xinglong site of national astronomical {2.,chinese academy of *** of our sample clusters are located in the halo of M31 and the most remote one is out to a projected radius of 78.75 kpc from the galactic *** all our sample clusters,we measured the lick absorption-line indices and radial *** is noted that most GCs in our sample are distinct from the HI rotation curve of galaxy M31,especially for B514,MCGC5,H12.and B517,suggesting that most of our sample clusters do not have a kinematic association with the star-forming young disk of the *** separately fitted the absorption line indices from the updated stellar population model of Thomas et *** two different tracks of Cassisi and Padova,by applying the χ2.minimization *** fitting results show that all our sample clusters are older than 10 Gyr,and metal-poor(2.38 ≤ [Fe/H] ≤ 0.91 dex).After merging the spectroscopic metallicity of our work with the previously published ones,we extended the cluster sample out to a projected radius of 117 kpc from the galaxy's *** found the metallicity gradient exists for all the confirmed clusters with a slope of 0.02. ± 0.001 dex kpc ***,the slope turns out to be 0.018 ± 0.001 dex kpc 1 for all the halo clusters,which is much *** we only consider the outer halo clusters with rp > 2. kpc,the slope becomes 0.010 ± 0.002.dex kpc 1 and if one cluster G001 is excluded from the outer halo sample,the slope is 0.004 ± 0.002.dex kpc ***,we conclude that the metallicity gradient for M31's outer halo clusters is not significant,which agrees well with previous findings.

关键词： galaxies individual(M31) — galaxies star clusters — globular clusters general — star clusters general

The emission positions of kHz QPOs and Kerr spacetime influence

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 114-116页

作者： zhang ChengMin1,WEI YingChun1,YIN HongXing1,zhao {2.,LEI YaJuan2.SONG liMing2.zhang Fan2.& YAN Yan3 1 national astronomical observatories,chinese academy of sciences,beijing {12.china 2.Institute of High Energy Physics,chinese academy of sciences,19B Yuquan Road,beijing 100049,china 3 Urumqi Observatory,national astronomical observatories,CAS,Urumqi 830011,china national astronomical {2. Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Urumqi Observatory National Astronomical Observatories CAS Urumqi China

Based the Alfven wave oscillation model(AWOM) and relativistic precession model(RPM) for twin kHz QPOs,we estimate the emission positions of most detected kHz QPOs to be at r=18+/-3 km(R/15 km),except Cir X-1 at r-30+/-5 km(R/15 km).For the proposed Keplerian frequency as an upper limit to kHz QPO,the spin effects in Kerr Spacetime are discussed,which have about a 5%(2.) modification for that of the Schwarzchild case for the spin frequency of 1000(400) *** application to the four typical QPO sources,Cir X-1,Sco X-1,SAX J1808.4-3658 and XTE 1807-2.4,is mentioned.

关键词： kHz QPO neutron star low-mass X-ray binaries

Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2, li ChunLai1, ZOU Yongliao1, zhang HongBo1, Lü Chang1, liU JianZhong1, liU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, zhao BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, zhang XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU lingli1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG liang1, zhang ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, li JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 national astronomical observatories, chinese academy of sciences, beijing 100012. china 2 Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, china 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 200083, china 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 210008, china 6 Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, beijing 100190, china national astronomical {2. Chinese Academy of Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 2.th, 2.07 at Xichang Satel{2.te Launch Center, and guided to crash on the Moon on March 1st, 2.09, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected {2.fe-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

The global image of the Moon obtained by the Chang'E-1:Data processing and lunar cartography

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Science china Earth sciences 2010年第8期53卷 1091-1102页

作者： li ChunLai1, liU JianJun1, REN Xin1, MOU lingli1, ZOU Yongliao1, zhang HongBo1, Lü Chang1, liU JianZhong1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, zhao BaoChang2. YANG JianFeng2. ZOU XiaoDuan1, WANG Min1, XU Chun1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG liang1, zhang ZhouBin1, ZHENG Lei1, ZHU XinYing1, li JunDuo1 & OUYANG ZiYuan11 national {12. observatories, chinese academy of sciences, beijing 100012. china 2.Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, china national astronomical {2. Chinese Academy of Sciences Beijing China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China

The global lunar image of the first phase of chinese Lunar Exploration Program is the first image that covered all over the surface of the Moon. It will serve as a critical foundation for succeeding exploration and scientific research. In this paper, the acquisition, characteristics, and data quality of Chang'E-1 CCD image data are described in detail. Also described are the methodology and procedure of data processing. According to rule of planetary cartography, the image data have been processed, geometrically corrected, and then mosaicked and merged in a scale of 1:2.5 million. The results of data processing and charting show that the image data of Chang'E-1 CCD and their geometric precision meet the demand of charting a map in the scale of 1:2.5 million. The relative geometric positioning precision of the global image is better than 2.0 m, and the absolute geometric positioning precision is slightly better than that of the ULCN2.05 and Clementine lunar basemap (V2.0). The plane positioning precision is approximately 100-1500 m. This global image proves to be the best global image of the Moon so far in terms of space coverage, image quality, and positioning precision.

关键词： Chang’E-1 lunar CCD data processing lunar image position lunar global image

Exploration of SDSS stellar database by AutoClass

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Science china(Physics,Mechanics & Astronomy) 2011年第9期54卷 1717-1726页

作者： YAN TaiSheng zhang yanxia {2. yongheng li Ji Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China College of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050016 China

AutoClass is an unsupervised Bayesian classification approach which seeks a maximum posterior probability classification for determining the optimal classes in large data sets. Using stellar photometric data from the Sloan Digital Sky Survey (SDSS) data release 7 (DR7), we utilize AutoClass to select non-stellar objects from this sample in order to build a pure stellar sample. For this purpose, the differences between PSF (point spread function) magnitudes and model magnitudes in five wavebands are taken as the input of AutoClass. Through clustering analysis of this sample by AutoClass, 617 non-stellar candidates are found. These candidates are identified by NED and SIMBAD databases. Most of the identified sources (13 from SIMBAD and 2. from NED respectively) are extragalactic sources (e.g., galaxies, HII, radio sources, infrared sources), some are peculiar stars (e.g., supernovas), and very few are normal stars. The extragalactic sources and peculiar stars of the identified objects occupy 94.1%. The result indicates that this method is an effective and robust clustering algorithm to find non-stellar objects and peculiar stars from the total stellar sample.

关键词： data analysis statistical method catalogues surveys star

New planetary nebulae in the outskirts of the Andromeda Galaxy discovered with the Guoshoujing Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2010年第7期10卷 599-611页

作者： Hai-Bo Yuan Xiao-Wei liu Zhi-Ying Huo Hui-Hua zhang Yong-Heng {2. Jian-Jun Chen Zhong-Rui Bai Hao-Tong zhang Hua-Wei zhang Ruben Garcia-Benito Mao-Sheng Xiang Hong-liang Yan Juan-Juan Ren Shi-Wei Sun Yong zhang Ye-Ping li Qi-Shuai Lu You Wang Ji-Jun Ni Hai Wang Department of Astronomy Peking University Beijing 100871 China Kavli Institute for Astronomy and Astrophysics Peking University Beijing 100871 China national astronomical {2. Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China Nanjing Institute of astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China

Planetary nebulae （PNe） are good tracers of the stellar populations, chemical composition and dynamics of their host galaxies. This paper reports the discovery of new PNe in the outskirts of the Andromeda Galaxy （M31） with the Guoshoujing Telescope （GSJT, formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope-LAMOST） during its early commissioning phase. In total, 36 candidates selected from SDSS photometry are confirmed in terms of their PN nature, including 17 new discoveries and another 19 previously known emission line objects. Their positions, spectra, radial velocities and m5007 magnitudes are presented. We discuss the potential for detecting more PNe in M 31 with GSJT＇s multi-object spectroscopy and the related applications in studies of the dynamics and chemistry of M 31 and its assemblage history.

关键词： galaxies individual (M 31) -- planetary nebulae general

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虚拟天文台的技术进展

天文学进展 2002年第4期20卷 302-311页

作者：崔辰州赵永恒赵刚张彦霞中国科学院国家天文台北京100012

虚拟天文台是在望远镜和探测器的研制技术、计算机网络技术取得突破性进展的条件下产生的,与最新的信息技术紧密结合成为其发展最鲜明的特点。用可扩展标记语言(简称XML)技术封装天文数据,把虚拟天文台建立在网格的体系结构之上是当今... 详细信息

虚拟天文台是在望远镜和探测器的研制技术、计算机网络技术取得突破性进展的条件下产生的,与最新的信息技术紧密结合成为其发展最鲜明的特点。用可扩展标记语言(简称XML)技术封装天文数据,把虚拟天文台建立在网格的体系结构之上是当今虚拟天文台技术发展的主流。按照目前虚拟天文台最具代表性的层次式体系结构分层介绍各个层次的相关技术,同时提出充分利用现有资源优势实施中国虚拟天文台计划的设想。

关键词：技术虚拟天文台标准仪器网络方法数据处理

New background quasars in the vicinity of the Andromeda Galaxy discovered with the Guoshoujing Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2010年第7期10卷 612-620页

作者： Zhi-Ying Huo Xiao-Wei liu Hai-Bo Yuan Hui-Hua zhang Yong-Heng {2. Jian-Jun Chen Zhong-Rui Bai Hao-Tong zhang Hua-Wei zhang Ruben Garcia-Benito Mao-Sheng Xiang Hong-liang Yan Juan-Juan Ren Shi-Wei Sun Yong zhang Ye-Ping li Qi-Shuai Lu You Wang Ji-Jun Ni Hai Wang Department of Astronomy Peking University Beijing 100871 China Kavli Institute for Astronomy and Astrophysics Peking University Beijing 100871 China national astronomical {2. Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China Nanjing Institute of astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China

We present preliminary analyses of spectra of quasar candidates in two Guoshoujing Telescope （GSJT, formerly named the Large Sky Area Multi-Object Fiber Spectroscopic Telescope - LAMOST） test fields near M 31 where one is close to the optical center of the disk and the other is towards the northeastern outskirts of the halo, obtained during the early stage of the GSJT commissioning in the last season of 2.09. Both fields contain background low-redshift quasar candidates selected from the SDSS photometry. In total, 14 new quasars with redshifts up to 2.and i magnitudes between 16.7 and 19.2. are discovered, including 7 within the 2.5° central region of M 31. We briefly discuss the potential applications of these newly discovered bright quasars.

关键词： galaxies individual (M31) -- quasars general -- quasars emission lines

Characteristics of plasma jet in laser driven magnetic reconnections

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Characteristics of plasma jet in laser driven magnetic recon...