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Thermal analysis of the baffle structure of the solar Space Telescope

Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1755-1764页

作者： LI Rong1,2,3.& WANG Sen1,3.1 national astronomical observatories,{3. {4. of sciences,Beijing 100012,China 2 Graduate University of {3. {4. of sciences,Beijing 10004.,China 3.key laboratory of solar activity,national astronomical observatories of chinese academy of sciences,Beijing 100012,China 1. national astronomical observatories Chinese Academy of Sciences Beijing 100012 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of Sciences Beijing 100012 China

The SST(Space solar Telescope) is an astronomical telescope with a primary mirror of 1 m in *** observes the sun with a small view field to ensure that its high spatial resolution imaging has 0.1″-0.15″ and high SNR(signal to noise ratio).Surrounding the small view field is still the sun,which is an intense source of both heat and stray *** baffles(the main baffle,the aperture,and the outer baffle),which are used to eliminate the stray light,will change the thermal flux in the SST and will weaken the effect of the thermal control *** this study,the compatibility analysis of the thermal effect of baffle structures in SST is *** GCF(Geometry Composing Function) and BRDF(Bidirectional Reflectance Distribution Function),which are two inherent related parameters in the compatibility analysis,are *** objective and method of the compatibility analysis are *** the thermal analysis software,the temperature fields are calculated for different lengths of the main baffle,different radii of apertures,different lengths of the outer baffle with a 3. tilt angle and 16' tilt angle,and different tilt angles of the outer baffle with a 200 mm length.A series of configurations and sizes of the baffles are studied with the goals of both thermal control and elimination of stray *** design of the baffle structure of SST is achieved:the main baffle of length 4.00 mm,the internal shield of radius 4.4.mm,the outer baffle of length 200 mm,and the outer baffle of tilt angle 3. are successfully *** paper presents the relationship between the thermal control design and stray light elimination plan in the *** aims of the optimal design of the baffle structure of SST are *** thoughts and methods of the optimal analysis are also useful for similar optical telescopes designed for solar observation.

关键词： baffle the main baffle the outer baffle GCF BRDF

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What does the Sun tell and hint now?

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Research in Astronomy and Astrophysics 2009年第9期9卷 959-965页

作者： Ke-Jun Li1,2 1 national astronomical observatories /Yunnan Observatory,{3. {4. of sciences,Kunming 650011,China 2 key laboratory of solar activity,national astronomical observatories,{3. {4. of sciences,Beijing 100012,China national astronomical observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China key laboratory of solar {3. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Some historical records, which have held since the beginning of modern solar activity cycles, are being broken by the present Sun： cycle 23.records the longest cycle length and fall time; latitudes of high-latitude sunspots belonging to a new cycle around the minimum time of the cycle are statistically the lowest at present, compared with those of other cycles; there are only one or no sunspots in a month appearing at high latitudes for 58 months, which is the first time that such a long duration has been observed. The solar dynamo is believed to be slowing down due to：（1） the minimum smoothed monthly mean sunspot number is the smallest since cycle 16 onwards, and even probably among all modern solar cycles; and （2） once the time interval between the first observations of two neighboring sunspot groups is larger than 14.d, it should be approximately regarded as an observation of no sunspots on the visible solar disk, called a spotless event. Spotless events occur with the highest frequency around the minimum time of cycle 24. and the longest spotless event also appears around the minimum time for observations of the Sun since cycle 16. Cycle 24.is expected to have the lowest level of sunspot activity from cycle 16 onwards and even probably for all of the modern solar cycles.

关键词： Sun: activity -- Sun: general -- sunspots

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Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4., ZHANG Shu 2 & ZHAO Gang 1 1 key laboratory of Optical Astronomy, {3. astronomical {4., chinese academy of sciences, Beijing 100012, China 2 key laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, Beijing 10004., China 3.Graduate University of the chinese academy of sciences, Beijing 10004., China 4.Department of Physics, Nanjing Normal University, Nanjing 210011, China 1. key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

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A comparative analysis on two solar proton events

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chinese Science Bulletin 2007年第1期52卷 47-51页

作者： LE GuiMing1,2,3.4. HAN YanBen2 & ZHANG YiJun3.1 key laboratory of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration, Beijing 100081, China 2 {3. astronomical {4., chinese academy of sciences, Beijing 100012, China 3.chinese academy of Meteorological sciences, China Meteorological Administration, Beijing 100081, China 4.{3. Center for Space Weather, China Meteorological Administration, Beijing 100081, China key laboratory of Radiometric Calibration and Validation for EnvironmentalSatellites China Meteorological Administration Beijing 100081 China

This paper presents a comparative analysis on the two solar Proton Events (SPE), which occurred on 14.July 2000 (Bastille Day) and 28 October 2003.(28OCT03. respectively. It is found that although the peak flux of the latter seemed to be greater than that of the former based on geostationary observations, the maximum intensities of the energetic protons (>10 MeV and 3. MeV) during the Bastille Day event were all higher than those of the 28OCT03.event according to the interplanetary observations. Further analysis indicated that the quantity of the seed particles, which could be accelerated to the energies exceeding 10 and 3. MeV by the Coronal Mass Ejection (CME)-driven shock on 14.July 2000, was far larger than that of the 28OCT03.event. In the Bastille Day case, when the CME approached to the height around 14.R⊙, the CME-driven shock would reach its maximum capacity in accelerating the solar en- ergetic protons (>100 MeV). In contrast, on 28 October 2003. when CME approached to the height about 58R⊙, the CME-driven shock reached its highest potential in accelerating the solar energetic protons of the same category. At this moment, the peak flux (>100 MeV) was about 155 pfu, which was much lower than 3.5 pfu measured on 14.July 2000. This demonstrated that in the Bastille Day event, the quantity of the seed particles, which could be accelerated to the energy beyond 100 MeV, was significantly larger than its counterpart in the 28OCT03.case. Therefore, the peak flux of an SPE event depends not only on the interplanetary intensity of the solar energetic particles, but also on the velocity of the associated CME-driven shock, and the quantity of the seed particles as well as on the interplanetary magnetic en- vironment. This paper also reveals that the magnetic sheath associated with ICME on 28 October 2003.captured a large number of solar energetic protons, including those having energy greater than 100 MeV.

关键词：太阳质子 CME 太阳耀斑太阳系

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solar release time of solar energetic particles and associated acceleration source in corona

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chinese Science Bulletin 2008年第2期53卷 161-168页

作者： LE GuiMing1,2,3.4. TANG YuHua1 & HAN YanBen4.1 Department of Astronomy, Nanjing University, Nanjing 210093. China 2 key {3. of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration, Beijing 100081, China 3.national Center for Space Weather, China Meteorological Administration, Beijing 100081, China 4.national {4. observatories, chinese academy of sciences, Beijing 100012, China Department of Astronomy Nanjing University Nanjing China key laboratory of Radiometric Calibration and Validation for Environmental Satellites China Meteorological Administration Beijing China national Center for Space Weather China Meteorological Administration Beijing China national astronomical observatories Chinese Academy of Sciences Beijing China

solar energetic particles (SEPs) are accelerated in corona at an early phase of solar energetic particle events (SEPE). The acceleration mechanism of SEPs in corona can only be inferred from an analysis of multi-band observational data, as the observation of SEPs is usually made around 1AU. In this context, people have investigated spectrums, charge state, solar release time (SRT), and multi-band data of SEPEs, in an attempt to judge the acceleration mechanism of SEPs. The SRT computation of SEPs is an important and commonly used approach to study the acceleration mechanism of SEPs in corona. This paper reviews some important findings concerning the SRT computation of SEPs, and analyzes different merits of each approach for such calculation, based on a range of SEPE case studies. This paper also analyzes and discusses both possible and actual acceleration mechanisms of a number of SEPEs, by calculating the SRT of the SEPEs. Finally, the paper summarizes the possible problems in studying an acceleration mechanism of SEPEs inferred from the SRT of SEP.

关键词：阳光释放时间加速度电晕太阳耀斑

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Anisotropic Beam Model for the Spectral Observations of Radio Burst Fine Structures on 1998 April 15

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chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 475-482页

作者： V.G. LedenevE-mail:yyh@*** , Yi-Hua Yan, and Qi-Jun Fu (national astronomical observatories, {3. {4. of sciences, Beijing 100012) (Institute of solar-Terrestrial Physics, Siberian Division of Russian {4. of sciences 664.3., Irkutsk, P. 0 Institute of solar-Terrestrial Physics Siberian Division of Russian Academy of Sciences 664033 Irkutsk P. O. Box 4026 Russia

A fine structure consisting of three almost equidistant frequency bands was observed in the high frequency part of a solar burst on 1998 April 15 by the spectrometer of Beijing astronomical Observatory in the range 2.6-3.8 GHz. A model for this event based on beam-anisotropic instability in the solar corona is presented. Longitudinal plasma waves are excited at cyclotron resonance and then transformed into radio emission at their second harmonic. The model is in accordance with the observations if we suppose a magnetic field strength in the region of emission generation of about 200 G.

关键词： Sun: radio radiation Sun: activity - Sun: corona

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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science China(Technological sciences) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2, WANG Shijie2, FENG Junming2, LI Chunlai1, OUYANG Ziyuan1,2, LIU Jianzhong1 & LI Xiaobiao2 1. national astronomical observatories, {3. {4. of sciences, Beijing 100012, China 2. State key laboratory of Environmental Geochemistry, Institute of Geochemistry, {3. {4. of sciences, Guiyang 550002, China 1. national astronomical observatories Chinese Academy of Sciences Beijing 100012 China 2. State key laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2+Fe2O4.and Fe2O3.type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 10.0, μ ′ = 1.2-1.5, μ ″ = 1.0-1.2, respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

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Properties of Broad Band Continuum of Narrow Line Seyfert 1 Galaxies

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chinese Journal of Astronomy and Astrophysics 2002年第6期2卷 501-524页

作者： Hong-Yan Zhou and Ting-Gui WangCenter for Astrophysics, University of Science and Technology of China, Hefei 23.026national astronomical observatories, {3. Academic of Science, Beijing {4. national astronomical observatories Chinese Academic of Science Beijing 100012

We have performed a statistical study of the properties of the broad band continuum of Narrow Line Seyfert 1 galaxies (NLS1s) by collecting ratio, infrared, optical and X-ray continuum data from various databases and compared the results with control samples of Broad Line Seyfert 1 galaxies (BLS1s). We find that the fraction (similar to 6%) of Radio Loud (RL) NLS1s is significantly less than that of BLS1s (similar to 13.), which is caused by the lack of radio-very-loud sources in the former. The rarity of RL NLS1s, especially radio-very-loud ones, is consistent with the scenario of small black hole and high accretion rate for NLS1s. Six new radio loud NLS1s are found and five RL NLS1 candidates are presented. In comparison with the BLS1s, the NLS1s tend to have stronger far infrared emission, cooler infrared colors and redder B - K color, which suggests that NLS1s are hosted by dust-richer nuclei. The NLS1s also show steeper soft X-ray spectrum and large soft X-ray to optical flux ratio, while a significant fraction show flat soft X-ray spectra. At least two factors can account for this, absorption and spectral variability. We also perform a correlation analysis between various broad band data. It is found that most correlations identified for NLS1s are also valid for radio quiet BLS1s: (1) the optical colors are anti-correlated with X-ray spectral index; (2) higher optical, Xray and NIR luminosity objects show bluer optical colors and red H - K color; (3. higher luminosity objects show warmer IRAS color; (4. the radio loudness correlates with B - K and X-ray to optical flux ratio. Radio loud objects behave somewhat differently in a few correlations.

关键词： galaxies : active galaxies : Seyfert radiation : continuum

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

SYMPATHETIC PARTIAL AND FULL FILAMENT ERUPTIONS OBSERVED IN ...

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强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Yuandeng Shen1,2,3.Yu Liu1,3.and Jiangtao Su3.1 Yunnan astronomical Observatory,chinese academy of {3.,Kunming 650011,China 2 Graduate University of chinese academy of {3.,Beijing 10004.,China 3.key laboratory of solar activity,national astronomical 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 23.minutes;it then accelerated to 102 km ***,this filament erupted successfully and caused a coronal mass *** the slow rising phase,various evidence for breakout-like 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

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太阳白光耀斑的射电辐射特征:运动Ⅳ型爆发和与耀斑后环共生的短周期脉动现象

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天文学报 1999年第4期40卷 419-427页

作者：谢瑞祥汪敏中国科学院云南天文台

通过１９９１年６月６日一个复杂的太阳活动事件（包括宽带射电运动Ⅳ型爆发、脉冲相伴生的白光耀斑、耀斑后环及其伴生的射电多重短周期（约１－４秒）脉动现象等）的分析，探讨了白光耀斑产生的射电辐射特征，根据太阳白光... 详细信息

通过１９９１年６月６日一个复杂的太阳活动事件（包括宽带射电运动Ⅳ型爆发、脉冲相伴生的白光耀斑、耀斑后环及其伴生的射电多重短周期（约１－４秒）脉动现象等）的分析，探讨了白光耀斑产生的射电辐射特征，根据太阳白光耀斑和射电运动Ⅳ型爆发产生的物理过程，着重讨论了射电运动Ⅳ型爆发、耀斑后环和短周期脉动现象。

关键词：太阳白光耀斑射电爆发耀斑后环射电脉动

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