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Evolution of the Level of Sunspot activity in solar Cycles I. Evolution in the Descending Phase

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chinese Journal of Astronomy and Astrophysics 2006年第3期6卷 354-362页

作者： Jia-Long Wang national astronomical observatories Chinese Academy of Sciences Beijing 100012

Taking the 13-point smoothed monthly sunspot number,Ri, and the deviation of the 13 associated monthly sunspot numbers from the smoothed one, Di, as a number-pair describing the global level of sunspot activity, the evolution of the level is statistically studied for the period from the month which is just 48 months before the minimum to the minimum in the descending phase, using the observed data of solar Cycles 10 to 22. Our results show （1） for 46 months （94%） of the studied 49 months it is found that for a given month, the distribution of the 13 pairs which come from the 13 solar cycles on a log Ri - Di plane may be fitted by a straight line with a correlation coefficient larger than the critical one at confidence level a = 5%, and for 36 months （73%） the fitting is even better, for a = 1%; （2） time variations of these two parameters and their correlations in the studied period can be described respectively by functions of time, whose main trends may be expressed by a linear or simple curvilinear function; （3） the evolutionary path of the level of sunspot activity may be represented by a logarithmic function as log/~ = 0.704 lnDi - 0.291.

关键词： Sun - sunspots - active level evolution

Magnetic Helicity Injection in solar Active Regions

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chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 96-112页

作者： Hong-Qi Zhang national astronomical observatories Chinese Academy of Sciences Beijing 100012

We present the evolution of magnetic field and its relationship with magnetic （current） helicity in solar active regions from a series of photospheric vector magnetograms obtained by Huairou solar Observing Station, longitudinal magnetograms by MDI of SOHO and white light images of TRACE. The photospheric current helicity density is a quantity reflecting the local twisted magnetic field and is related to the remaining magnetic helicity in the photosphere, even if the mean current helicity density brings the general chiral property in a layer of solar active regions. As new magnetic flux emerges in active regions, changes of photospheric cur- rent helicity density with the injection of magnetic helicity into the corona from the subatmosphere can be detected, including changes in sign caused by the injection of magnetic helicity of opposite sign. Because the injection rate of magnetic helicity and photospheric current helicity density have different means in the solar atmosphere, the injected magnetic helicity is probably not proportional to the current helicity density remaining in the photosphere. The evidence is that rotation of sunspots does not synchronize exactly with the twist of photospheric transverse magnetic field in some active regions （such as, delta active regions）. They represent different aspects of magnetic chirality. A combined analysis of the observational magnetic helicity parameters actually provides a relative complete picture of magnetic helicity and its transfer in the solar atmosphere.

关键词： Sun: activity Sun: magnetic fields

Comparisons of Infrared Colors and Emission-line Intensities between Two types of Seyfert 2 Galaxies

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chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 408-418页

作者： Lin-Peng Cheng, Yong-Heng Zhao and Jian-Yan Weinational astronomical observatories, chinese academy of sciences, beijing 100012 national astronomical observatories CAS NAOC Beijing China

We study the relation between the infrared colors, [OIII] emission lines, gaseous absorbing column density (NH),and the detectability of the polarized (hidden) broad-line region (HBLR) in a large sample of 75 Seyfert 2 galaxies (Sy2s). From the indicators of star-formation activity, f60/f100 and LFIR/LB, we find some evidence that the Sy2s without HBLR show higher star-formation activities than those with HBLR, in agreement with previous prediction. Also, we confirm that the HBLR Sy2s tend to have a larger luminosity ratio of the core to the host galaxy, suggesting that the HBLR Sy2s display more powerful AGN activity. However, the level of obscuration found in previous papers is nearly indistinguishable between the two types of Sy2s. The results support the statement that the non-HBLR Sy2s, with a weaker core component and a stronger star-formation activity component, are intrinsically different from the HBLR Sy2s, which are Sy1 systems with a hidden powerful AGN core and a low star-formation activity. The indications are that the non-HBLR Sy2s might be at an earlier evolutionary phase than the HBLR Sy2s.

关键词： galaxies: active - galaxies: Seyfert - polarization - star formation

A puzzle of the radio-quiet quasar PG 1407+265:Are optical and X-ray emissions produced from a relativistic jet?

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Science china(Physics,Mechanics & Astronomy) 2011年第1期54卷 183-186页

作者： CHEN Liang 1,2,3 & BAI JinMing 1,2 1 national astronomical observatories/Yunnan Observatory,chinese academy of sciences,Kunming 650011,china 2 key laboratory for the Structure and Evolution of Celestial Objects,chinese academy of sciences,Kunming 650011,china 3 Graduate University of chinese academy of sciences,beijing 100049,china chinese academy of sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***) Graduate University of chinese academy of sciences Beijing China (GRID:grid.458514.9) chinese academy of sciences National Astronomical Observatories/Yunnan Observatory Kunming China (GRID:grid.9227.e) (ISNI:***) chinese academy of sciences Key Laboratory for the Structure and Evolution of Celestial Objects Kunming China (GRID:grid.9227.e) (ISNI:***)

PG 1407+265 is a radio quiet quasar that has a relativistic *** this report,we show some peculiar properties of its optical and X-ray emissions,which indicate possible non-thermal origins produced from the *** use a simple synchrotron + synchrotron self Compton (SSC) model to fit the emissions with different ratios of energy densities between the magnetic field and electrons (η≡U B/U e),which predicts a different γ-ray *** First LAT AGN Catalog (1LAC) did not include PG 1407+265,which indicates an upper limit of γ-ray *** upper limit constrains the ratio to be unreasonably large (η≥10 4-5).This inversely indicates that the optical and X-ray emissions may not be produced from the beaming *** discuss the physical implications of these results.

关键词： active galactic nuclei jet non-thermal emission PG 1407+265

Petrology and mineral chemistry of new ureilites found in Grove Mountains, Antarctica

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Progress in Natural Science:Materials International 2008年第4期18卷 431-439页

作者： Bingkui Miaoa,b,, Yangting Linb, Guiqin Wangc, Daode Wangc, Ziyuan Ouyangd a key laboratory of Geological Engineering Center of Guangxi Province, Guilin University of Technology, Guilin 541004, china b State key laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china c key laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510640, chinad national astronomical observatories, chinese academy of sciences, beijing 100012, china key laboratory of Geological Engineering Center of Guangxi Province Guilin University of Technology Guilin 541004 China State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China key laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China national astronomical observatories Chinese Academy of Sciences Beijing 100012 China

Petrography and mineral chemistry of two new ureilites, GRV 021512 and 022931, from the Grove Mountains, Antarctica, are reported in this paper. GRV 021512 exhibits a typical ureilite texture, and consists of 48.3% olivine, 9.4% pigeonite and 38.1% carbo- naceous interstitial material and/or reduction product. GRV 022931 has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3% carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed.

关键词： Meteorite Achondrite Ureilite Diamond Antarctica

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, national astronomical observatories, chinese academy of sciences, beijing 100012, china 2 key laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, beijing 100049, china 3 Graduate University of the chinese academy of sciences, beijing 100049, china 4 Department of Physics, Nanjing Normal University, Nanjing 210011, china chinese academy of sciences Key Laboratory of Optical Astronomy National Astronomical Observatories Beijing China (GRID:grid.9227.e) (ISNI:***) chinese academy of sciences Key Laboratory for Particle Astrophysics Institute of High Energy Physics Beijing China (GRID:grid.9227.e) (ISNI:***) Graduate University of the chinese academy of sciences Beijing China (GRID:grid.458514.9) chinese academy of sciences Key Laboratory for Particle Astrophysics Institute of High Energy Physics Beijing China (GRID:grid.9227.e) (ISNI:***) Nanjing Normal University Department of Physics Nanjing China (GRID:grid.260474.3) (ISNI:***) chinese academy of sciences Key Laboratory of Optical Astronomy National Astronomical Observatories Beijing China (GRID:grid.9227.e) (ISNI:***)

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

Possible effect of solar activity on variation of the tree-rings of a 500 a platycladus orientalis at the Mausoleum of Emperor Huang

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Science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 631-639页

作者： FENG Bo1,2 & HAN YanBen1 1 Xi’an Institute of Posts & Telecommunications,Xi’an 710061,china 2 national astronomical observatories,chinese academy of sciences,beijing 100012,china Xi’an Institute of Posts & Telecommunications Xi’an China national astronomical observatories Chinese Academy of Sciences Beijing China

The variation of the tree-ring's index of a platycladus orientalis at the Mausoleum of Emperor Huang and of a long series of sunspots relative number during AD1470-1974 are analyzed by using the wavelet power spectrum method,and their variation characters are also discussed. It is determined that the tree-ring's variation has cycles of approximate 2-7,11,93 and 150 a. Two data series are used for analyzing sunspot relative number(SSN) variation. First,the analysis of the annual average SSN during AD1700-1974 proved that variation cycles are about 11,50,and 93 a; then,the data during AD1465-1975 obtained from the decadal average SSN train over 7000 a reconstructed on the geomagnetic data is analyzed and its variation cycles are about 50,90,and 160 a. Besides the tree-rings cycle of 2-7 a is commonly considered to be related to ENSO,while 11 a cycle is related to solar Schwabe cycle; in addition,it is possible that the cycles of 90 and150 a are likely to be related to solar Gleissberg cycle and Suess cycle. The correlations between them are possibly due to the effect of solar activity on the climate and additionally on the tree's growth.

关键词： tree-ring solar activity climate change wavelet spectrum

Calculations for the Pre-Calibration of LAMOST Active Optics

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chinese Journal of Astronomy and Astrophysics 2005年第3期5卷 302-314页

作者： Yong Zhang and Xiang-Qun Cui national astronomical observatories / Nanjing Institute of astronomical Optics & Technology, chinese academy of sciences, Nanjing 210042 Graduate School of the chinese academy of sciences, beijing 100039 national astronomical observatories/Nanjing Institute of astronomical Optics & Technology Chinese Academy of Sciences Nanjing 210042

Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) is one of the major on-going national large scientific projects in china. Active optics is a key technology for the LAMOST with which the thin-mirror active optics and segmented-mirror active optics are tied in. A pre-calibration method considering all active forces and displacements specially for LAMOST has been developed in early 2004. We give a detailed mathematical derivation and calculation including numerical simulation and computer program realization of the pre-calibration method of LAMOST open-loop control for the third-order aspherical aberration. We have also carried out calculations on the application of the pre-calibration method and the parameters of actuator design in LAMOST active optics in observation mode, including estimations of the actuator ranges, the interval of active optics correction and the ranges and trends of load changes on all the actuators during LAMOST tracking a given star.

关键词： active optics telescopes instrumentation

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 national astronomical observatories, chinese academy of sciences, beijing 100012, china 3 chinese academy of Meteorological sciences, china Meteorological Administration, beijing 100081, china 4 national Center for Space Weather, china Meteorological Administration, beijing 100081, china key laboratory of Radiometric Calibration and Validation for Environmental Satellites 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 30 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 30 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 355 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