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Multi-epoch X-ray observations of the narrow-line Seyfert 1 galaxy SDSS J160508.87+32.92..4 with XMM-Newton

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 207-211页

作者： AI Yanli1,2.3,YUAN WeiMin1,2.ZHOU HongYan4,5 & WANG JianGuo1,2.3 1 national {2. 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 the chinese Academy of sciences,Beijing 100049,china 4 Center for Astrophysics,University of Science and Technology of china,Hefei 2.002.,china 5 Joint Institute of Galaxies and Cosmology,SHAO and USTC,Shanghai 2.0030,china 1. national astronomical {2./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 the chinese Academy of sciences Beijing 100049 China 4. Center for Astrophysics University of Science and Technology of China Hefei 230026 China 5. Joint Institute of Galaxies and Cosmology SHAO and USTC Shanghai 200030 China

We present results of multi-epoch XMM-Newton observations separated by several years of the narrow-line Seyfert 1(NLS1) galaxy,SDSS J160508.87+*** NLS1 showed X-ray flux variations on timescales of years as well as low amplitude variations on timescales as short as hours,while the X-ray spectral shape remained essentially *** spectrum shows a significant soft X-ray *** model of reflection from an ionized disc,that is dominant in the whole XMM-Newton bandpass,provides the best description of the observed spectra for all the observations,though alternatives such as Compton scattering(T-0.2. {2.V) cannot be ruled out in a statistical *** the disc reflection model,the observed variations may originate either from the change in the reflection fraction,or from the variability of the intrinsic X-ray luminosity.

关键词： galaxies:active Seyfert X-rays individual

The Influence of Panel Gaps on the System NoiseTemperature of the FAST

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chinese Journal of Astronomy and Astrophysics 2001年第2期1卷 190-194页

作者： Yan Su and Guo-Ding li (1 Beijing astronomical {2., national astronomical observatories, chinese Academy of sciences, Beijing 100012.2.The Laboratory of Microwave and Digital Communication Technology, Tsinghua University, Beijing 100084) The Laboratory of Microwave and Digital Communication Technology Tsinghua University Beijing 100084

A Five-hundred-meter Aperture Spherical Telescope (FAST), the largest single dish in the world, is proposed to be built in one of the karst depressions in Guizhou province. The main spherical reflector is to consist of about two thousand small panels, which can be adjusted to fit a paraboloid in real time. There are many slit-li{2. gaps across the aperture due to manufacturing errors thermal effects and deviations between a sphere and a paraboloid. The influence of the energy leakage of the narrow gaps on the system noise temperature of the FAST reflector is discussed in this paper.

关键词： telescopes - methods: analytical - energy leakage

Magnetic Loop Oscillation Associated with a Large Type-Ⅳμ Burst and Millisecond Spike Emission

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天文研究与技术 1999年第S1期 424-427页

作者： Chen Xiaojuan, Ji Shuchen (Beijing astronomical observatory, The {2. Academy of sciences, Beijing 100080, china) (yunnan observatory, The {2. Academy of sciences, kunming 650011, china) (national astronomical observatories, {2. Academy of S

A rare large Type Ⅳμ burst, appeared above active region NOAA/USAF 52.8 was observed at yunnan observatory with Phoenix Ⅱ Microwave Spectrometer at three frequencies (4 00, 2.84 and 1 42.GHz) on December 16, 1988. The burst consisted of 5 main peaks with a quasiperiod of 12.5 min, on which many complex mil{2.second spike emissions were superimposed. Within the first main peak there were 8 secondary peaks with a quasi period of 98s (at 4 00 GHz), 72. (2.84 GHz) and 60s (1 42.GHz). A semi quantitative explanation is given for the variation of the quasi period with frequency in terms of MHD modulated oscillations in the magnetic flux tube.

关键词： Type Magnetic Loop Oscillation Associated with a Large Burst and Millisecond Spike Emission

Spectral Analysis of the Flare of 1998 November 11 based on the Multi-cloud Model

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chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 92-102页

作者： Xiao－MaGu Ming－DeDing yunnanobservatory NationalAstronomicalObservatoriesCASKunming650011 DepartmentofAstronomy NanjingUniversityNanjing210093

We have obtained 2. spectra of Ha and CaII λ8542. for the flare of 1998 November 11, and derived its 2. velocity field and integrated intensity field. The velocity distribution shows that the red-shift and blue-shift velocities lie respectively in the northern and southern parts of the flare and that the maximum velocity seems to be located in two footpoints of the flare loop system. The integrated intensity distribution shows that the CaIIλ8542. line is formed at a lower height than the Ha line, we used 'multi-cloud model' (MCM) to obtain four parameters for the two lines (Doppler width, △λD, Doppler shift, △λ0, line source function, S, and optical depth at the line center, TO). We also estimated the column number densities of hydrogen at the second level, N2. and of the ionized calcium at the third level, N3, as well as the kinetic temperature, Tc. The wide Hα profile at the loop top may be explained by an overlapping of two or more elementary profiles. It is shown that the uncertainty in calibration does not affect the derived Doppler shift and line broadening, only the source function and optical depth.

关键词： Sun: activity-Sun: flares-methods: data analysis

About the O'Connell Effect of a Close Binary

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天文研究与技术 1999年第S1期 378-382页

作者： liu Qingyao, Yang Yulan (yunnan {2., The chinese Academy of sciences, kunming 650011, china) (United Laboratory of Optical Astronomy, The chinese Academy of sciences, kunming 650011, china) (national {12. observatories, The chinese Acad

Based on the hypothesis that the circumstellar matter of a binary system is captured by its components a theoretical model for explaining the O’Connell effect of the colse binary is given in this present article.

关键词： About the O’Connell Effect of a Close Binary In

Observations of Microwave Ultra-Fast Absorption Phenomena Above Solar Active Region

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天文研究与技术 1999年第S1期 428-432页

作者： Chen Xiajuan, Ji Shuchen (Beijing astronomical observatory, The {2. Academy of sciences,Beinjing 100080, china) (yunnan observatory, The {2. Academy of sciences, kunming 650011, china) (national astronomical observatories, The {2. Academy o

While we process observational data of the Flares 2., two rare phenomena of microwave ultra fast absorption (MUFA) are found for the first time. They occurred at 3 67 GHz and 4 00 GHz in the atmospheric layers above both active regions of NOAA/USAF 4808 and 5060 in the interval 05 h50 m17 s～05 h50 m2. s UT on May 19, 1987 and 07 h38 m50 s～07 h38 m58 s UT on june 2., 1988, respectively. These absorption phenomena were observed with Phoenix Ⅱ Micowave Spectrometer at three frequencies (1 42. 2.84 and 3 67 GHz) and (1 42. 2.84 and 4 00 GHz) at yunnan {2.. Spike emissions appeared at both 2.84 GHz and 1 42.GHz. The notable observational characteristics of both absorption phenomena are given. A possible absorption mechanism of MUFA is discussed.

关键词： Observations of Microwave Ultra-Fast Absorption Phenomena Above Solar Active Region

Gyrosynchrotron Process of a Rare Large Type-Ⅳμ Burst Associated with Coronal Mass Ejection

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天文研究与技术 1999年第S1期 452-456页

作者： Ji Shuchen, Chen Xiaojuan (Beijing astronomical observatory, The {2. Academy of sciences, Beijing 100080, china) (yunnan observatory, The {2. Academy of sciences, kunming 650011, china) (national astronomical observatories, The {2. Academy

A large Type Ⅳμ solar radio burst was observed at yunnan observatory on December 16, 1988. The burst was associated by a coronal mass ejection (CME) with the radio signature of Type Ⅱ and Type Ⅳ bursts. On the basis of Beijing Huairou magnetogram of AR52.8, power law distribution of electrons of the source region is calculated. It is suggested that the Type Ⅳμ burst associated with CME was due to the gyrosynchrotron radiation of high energy electrons trapped by magnetic field. Finally, some quantitative and qua{2.tative explanations are proposed.

关键词： Mass Associated with Coronal Mass Ejection Burst Gyrosynchrotron Process of a Rare Large Type

Microwave Millisecond Spikes on July 30, 1997

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天文研究与技术 1999年第S1期 461-466页

作者： Wang M., Xie R. X.$$$$1 (Beijing astronomical observatory, The {2. Academy of sciences, Beijing 100012. china) 2.(yunnan astronomical observatory, The {2. Academy of sciences, kunming 650011, china) 3 ({12. astronomical observatories, The Ch

The characteristics of the millisecond spikes with short durations and weak flux densities which were observed with high time resolution (1 ms) during a great type Ⅳ solar radio burst of 1990 July 30 are introduced. The time profiles of the spikes are statistically analyzed and the parameters of the spike source are also estimated.

关键词： Microwave Millisecond Spikes on July 30

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, chinese Academy of sciences, Beijing 100012. china 2. State key Laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese Academy of sciences, Guiyang 550002. china 1. national astronomical {2. 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.Fe2.4 and Fe2.3 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.