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金牛T型星的红外光谱

天文学报 1999年第4期40卷 407-418页

作者：陈培生王锋汪洵浩中国科学院云南天文台

给出２６个金牛Ｔ型星的ＩＲＡＳ低分辨率红外光谱．根据这些光谱讨论了它们有关的性质和所处环境．分析发现硅酸盐尘埃在金牛Ｔ

关键词：金牛T型星红外光谱物理性质物理环境恒星

The Chiralities of Three Filaments in AR7500

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天文研究与技术 1999年第S1期 433-437页

作者： Jiang Yunchun 1,2.3 , Luan Di 1,2., lin Ganghua 1,3 , Wang Jingxiu 1,3 1 (national {2. observatories, The chinese Academy of sciences, Beijing 100012. china) 2.(yunnan observatory, The chinese Academy of sciences, kunming 65001

An analysis of structure and evolution of three filaments in AR7500 ON May, 1993 is presented. The three filaments show the following remarkable peculiarities: 1) a sinistral filament lies between two dextral filaments and meets them at two cusps. One of the cusps is rooted in positive polarity plage region while the other in a small decaying spot with negative polarity. 2. Both chromospheric plagette associated fibrils near the filaments and the transverse magnetic fields of the photosphere beneath the filaments almost parallel to the long axis of these filaments, suggesting the dominance of axial field of filaments; the spots near filament’s ends, however, do not show clearly counterclockwise or clockwise superpenumbral fibril pattern. 3) The three filaments do not merge into a single filament during 8 day observation. This can be explained by considering that the magnetic fields along their long axes are in different directions at two cusps. When one of dextral filaments and the sinistral filarment eventually dissipate into fibrils connecting the opposite polarity regions, their jointing cusps can be still clearly observed due to their opposite chiralities.

关键词： Sun: filament Sun:magnetic field

SYMPATHETIC PARTIAL AND FULL FILAMENT ERUPTIONS OBSERVED IN ONE SOLAR BREAKOUT EVENT

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SYMPATHETIC PARTIAL AND FULL FILAMENT ERUPTIONS OBSERVED IN ...

Searching for Variable Stars in the Field of NGC 7789

强化科技基础推进气象现代化——第2.届中国气象学会年会

作者： Yuandeng Shen1,2.3,Yu liu1,3,and Jiangtao Su3 1 yunnan {2. observatory,chinese Academy of sciences,kunming 650011,china 2.Graduate University of chinese Academy of sciences,Beijing 100049,china 3 key Laboratory of Solar Activity,{12. {2. observatories,chinese Academy of Science,Beijing 100012.china

We report two sympathetic solar eruptions including a partial and a full flux rope eruption in a quadrupolar magnetic region where a large and a small filament resided above the middle and the east neutral lines,*** large filament first rose slowly at a speed of 8 km s-1 for 2. minutes;it then accelerated to 102.km ***,this filament erupted successfully and caused a coronal mass *** the slow rising phase,various evidence for breakout-li{2. external reconnection has been identified at high and low temperature *** eruption of the small filament started around the end of the large filament’s slow *** filament erupted partially,and no associated coronal mass ejection could be *** on a potential field extrapolation,we find that the topology of the three-dimensional coronal field above the source region is composed of three low-lying lobes and a large overlying flux system,and a null point located between the middle lobe and the overlying antiparallel flux *** propose a possible mechanism within the framework of the magnetic breakout model to interpret the sympathetic filament eruptions,in which the magnetic implosion mechanism is thought to be a possible link between the sympathetic eruptions,and the external reconnection at the null point transfers field lines from the middle lobe to the lateral lobes and thereby leads to the full(partial) eruption of the observed large(small) *** possible mechanisms are also discussed *** conclude that the structural properties of coronal fields are important for producing sympathetic eruptions.

关键词： Sun:activity-Sun:coronal mass ejections(CMEs)-Sun:filaments prominences-Sun:flares-Sun:magnetic topology

来源： cnki会议评论

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chinese Journal of Astronomy and Astrophysics 2003年第2期3卷 151-165页

作者： Xiao-Bin Zhang, li-Cai Deng, Yu Xin and Xu Zhounational {2. observatories, chinese Academy of sciences, Beijing 100012.CAS-PKU Joint Beijing Astrophysics Center, Beijing 100871 national astronomical {2. CAS NAOC Beijing 100012 China []CAS-PKU Joint Beijing Astrophysics Center Beijing 100871

We present the results of a time-series CCD photometric survey of variable stars in the field of the open cluster NGC 7789. In a field of about one degree centering on the cluster, a total of 2. new variable stars are discovered (14 W UMa systems, nine EA-type eclipsing binaries, one RR Lyr star, and four unclassified). In addition, we recovered 11 old variables previously discovered by other authors. Preliminary parameters are given for some of these variables.

关键词： open clusters: individual (NGC 7789) - stars: variables (general) - binaries: general

一个复杂太阳射电爆发及其微波源和远紫外冕环特征的初步研究

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天文学报 2004年第4期45卷 389-401页

作者：王霖谢瑞祥汪敏许春刘玉英中国科学院国家天文台云南天文台昆明650011 中国科学院国家天史台北京100012

利用太阳射电宽带频谱仪(0.7-7.6 GHz)于2.01年10月19目观测到的复杂太阳射电大爆发,呈现出许多有趣的特征.结合NoRH(Nobevama Radio Heliograph)的高空间分辨率射电成像观测及TRACE(Transition Region and Coronal Explorer)在远紫外(EUV)波段的高空间分辨率成像观测资料,分析了该爆发的射电频谱特征和微波射电源的演化以及它们与复杂的EUV日冕环系统的关系.该爆发是一个双带大耀斑的射电表征.前一部分以宽带(从厘米到米波)爆发为主,机制是回旋同步辐射,所对应的是环足源的辐射;后一部分以窄带(分米到米波)分米波爆发为主,机制是等离子体辐射和回旋共振辐射的联合,对应的是环顶源的辐射.

关键词：太阳射电爆发射电源耀斑日冕观测资料微波源演化 EUV 米波宽带

Lossless Compression Method for the Magnetic and Helioseismic Imager(MHI)Payload

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Research in Astronomy and Astrophysics 2024年第4期24卷 214-221页

作者： li-Yue Tong Jia-Ben lin Yuan-Yong Deng Kai-Fan Ji {2.-Feng Hou Quan Wang Xiao Yang national astronomical {2. Chinese Academy of SciencesBeijing 100101China key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China yunnan observatories Chinese Academy of SciencesKunming 650216China

The Solar Polar-orbit observatory(SPO),proposed by chinese scientists,is designed to observe the solar polar regions in an unprecedented way with a spacecraft trave{2.ng in a large solar inc{2.nation angle and a small ***,one of the most significant challenges {2.es in ultra-long-distance data transmission,particularly for the Magnetic and He{2.oseismic Imager(MHI),which is the most important payload and generates the largest volume of data in *** this paper,we propose a tailored lossless data compression method based on the measurement mode and characteristics of MHI *** background out of the solar disk is removed to decrease the pixel number of an image under *** predictive coding methods are combined to e{2.minate the redundancy uti{2.zing the correlation(space,spectrum,and polarization)in data set,improving the compression *** results demonstrate that our method achieves an average compression ratio of *** compression time is also less than the general observation *** method exhibits strong feasibi{2.ty and can be easily adapted to MHI.

关键词： methods:data analysis techniques:image processing Sun:magnetic fields Sun:photosphere

1998年4月15日射电爆发中的微波Ⅲ型爆发

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天文学报 2001年第4期42卷 382-389页

作者：段长春汪敏谢瑞祥颜毅华中国科学院云南天文台昆明650011 中国科学院国家天文台北京100012

详细介绍了北京天文台 2..6— 3 .8GHz太阳射电频谱仪在 1 998年 4月 1 5日观测到的一群微波Ⅲ型爆发 .它们具有宽频带 (>1 0 0MHz)、短时标 (<1 0 0ms)、高偏振 (1 0 0 % )、短周期脉动 (百毫秒 )、内向快速频率漂移 (高于 1GHz/s)等... 详细信息

详细介绍了北京天文台 2..6— 3 .8GHz太阳射电频谱仪在 1 998年 4月 1 5日观测到的一群微波Ⅲ型爆发 .它们具有宽频带 (>1 0 0MHz)、短时标 (1 0 0ms)、高偏振 (1 0 0 % )、短周期脉动 (百毫秒 )、内向快速频率漂移 (高于 1GHz/s)等显著特征 .讨论了它的观测特征、时间轮廓和脉动现象 ,认为该群微波Ⅲ型爆发起源于等离子体基波辐射 .

关键词：太阳微波Ⅲ型爆发等离子体辐射 1998年射电频谱仪

Test observations that search for metal-poor stars with the Guoshoujing Telescope (LAMOST)

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Research in Astronomy and Astrophysics 2010年第8期10卷 753-760页

作者： Hai-Ning li Gang Zhao Norbert Christlieb A-li Luo Jing-Kun Zhao Yong-Heng Zhao Jian-jun Chen Zhong-Rui Bai key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of chinese Academy of sciences Beijing 100049 China Zentrum fur Astronomie der Universitat Heidelberg Landessternwarte Konigstuhl 12 69117 Heidelberg Germany

Metal-deficient stars are regarded as fossils of the early generation of stars and therefore make crucial observational targets related to stellar astrophysics. They provide fundamental information and insights on properties of the very early stage of the chemical history of the Galaxy and have been investigated for decades. The unique design of the Guoshoujing Telescope （LAMOST）, such as its large field and multi-object observational capability, enables it to be an excellent tool for searching for these metal-poor stars in the Milky Way. This work reports the result of test observations which search for metal-poor stars with LAMOST, during which nine candidate metal-poor stars with [Fe/H] ≤ - 1.0 were newly detected based on the low-resolution spectroscopic observations of the LAMOST commissioning data. The sample of stars demonstrates the efficiency of selecting from the input catalog, as well as the ability of LAMOST to enlarge the sample of metal-poor stars in the Milky Way. Furthermore, the sample of stars could be used for future calibrations of the LAMOST stellar pa- rameter pipeline.

关键词： Galaxy stellar content -- surveys -- stars Population Ⅱ

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日冕分米波射电甚短周期脉动的观测证据

天文学报 2003年第2期44卷 139-146页

作者：谢瑞祥汪敏施硕彪许春李维华颜毅华中国科学院国家天文台云南天文台昆明650011 中国科学院国家天文台北京100012

利用国家天文台云南天文台“分米波(700—1500 MHz)射电频谱仪”和“四波段太阳射电高时间分辨率同步观测系统”分别于2.01年6月2.日和1990年7月30日观测到了两个稀少事件,前者是一个小射电爆发,其上升相伴随有短周期(约2.、40和100毫秒... 详细信息

利用国家天文台云南天文台“分米波(700—1500 MHz)射电频谱仪”和“四波段太阳射电高时间分辨率同步观测系统”分别于2.01年6月2.日和1990年7月30日观测到了两个稀少事件,前者是一个小射电爆发,其上升相伴随有短周期(约2.、40和100毫秒)的脉动,后者是一个射电大爆发,在2.40 MHz上产生了周期约30毫秒的射电脉动。还着重讨论其甚短周期(如2.—40毫秒)的脉动现象,甚短周期脉动可能是归因干起源在日冕深处不稳定区域的哨声波束周期链对射电辐射的凋制,或沉降电子束驱动的静电高混杂波,经由波-波非线性相互作用导致甚短周期的射电脉动。

关键词：日冕射电辐射磁场脉动