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VIBI Observations of Two Quasars at 1.3cm

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天文研究与技术 1999年第S1期 299-304页

作者： Su Bumei, li Yongsheng ( yunnan {2., The chinese academy of sciences, kunming 650011, china ) ( national astronomical Observatories, The chinese academy of sciences, Beijing 100012. china ) Braath L.B. ( Center for Imaging Technologies, Halmst

The quasars, 0748+12. and 2.0}+158 (3C 454 3),have been observed at 1 3cm by using a global VLBI network. We have obtained the images of the quasars with a resolution higher than 0″ 001. The brightness distribution is revealed in the nuclear region of the quasars. The radio emission FWHM from 0748+12. is 0 61×0 2. mas. 2.0}+158 shows a nucleus-jet structure, and the nuclear region is elongated in the direction PA=-130°, The quasar can be fitted with 4 Gaussian components. The most west and east components are separated by 0 8mas (3pc). The integrated flux density in the nuclear region is 6 138Jy. The most east component shows the highest brightness, and its flux is ～4 11Jy (in 67% of the total detected flux), concentrated in the area of 0 16×0 01 mas. This causes the brightness temperature up to 2.6×10 12.K.

关键词： VIBI Observations of Two Quasars at 1.3cm

Observations of Ultraluminous IRAS Galaxies at 2.cm

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天文研究与技术 1999年第S1期 305-308页

作者： li Yongsheng, Su Bumei ( yunnan {2., The chinese academy of sciences, kunming 650011, china ) ( national astronomical Observatories, The chinese academy of sciences, Beijing 100012. china ) Norris R.P. (Australia Telescope national Facility,

An ultraluminous IRAS galaxy sample has been observed at 2.cm using the Australia Compact Array (AT). The far infrared luminosity in the sample, log L FIR (L ⊙), is>11 8 ( H 0=50 km s -1 Mpc -1 , q 0=0 5 ). (Radio emission is detected from 19 sources among 37 IRAS galaxies. The radio parameters, for example, peak position, radio flux, etc, are obtained. The radio power P 2.cm in the sample is in the range 2. 92.cm (W/Hz) 2. 8. The paper presents the preliminary observational results on the sample at 2.cm.

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Quasi-2. weak lensing cosmological constraints using the PDF-SYM method

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Science china(Physics,Mechanics & Astronomy) 2024年第7期67卷 44-58页

作者： Zhenjie liu jun Zhang Hekun li Zhi Shen Cong liu Department of Astronomy Shanghai Jiao Tong UniversityShanghai 200240China Shanghai key Laboratory for Particle Physics and Cosmology Shanghai 200240China Shanghai astronomical observatory Chinese Academy of SciencesShanghai 200030China

Cosmic shear statistics,such as the two-point correlation function(2.CF),can be evaluated with the PDF-SYM method instead of the traditional weighted-sum *** makes use of the full PDF information of the shear estimators,and does not require weightings on the shear estimators,which can in principle introduce additional systematic *** work presents our constraints on S8and?mfrom the shear-shear correlations using the PDF-SYM *** data we use is from the z-band images of the Dark Energy Camera Legacy Survey(DECa LS),which covers about 10000 deg2.ith more than 100 million *** shear catalog is produced by the Fourier Quad method,and well tested on the real data itself with the field-distortion *** main approach is called quasi-2. as we do use the photo-z information of each individual galaxy,but without dividing the galaxies into redshift *** mainly use galaxy pairs within the redshift interval between 0.2.and 1.3,and the angular range from 4.7 to 180 *** analysis yields S8=0.762.0.02. and?m=0.2.4±0.075,with the baryon effects and the intrinsic alignments *** results are robust against redshift *** check the consistency of our results by deriving the cosmological constraints from auto-correlations ofγ1andγ2.eparately,and find that they are consistent with each other,but the constraints from theγ1component are much weaker than that fromγ*** implies a much worse data quality ofγ1,which is likely due to additional shear uncertainties caused by CCD electronics(according to the survey strategy of DECa LS).We also perform a pure 2. analysis,which gives S8=0.81_(-0.04)^(+0.03)and?m=0.2._(-0.05)^(+0.06).Our findings demonstrate the potential of the PDF-SYM method for precision cosmology.

关键词： weak lensing shear-shear correlations cosmological parameters observations analysis

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粘滞对黑洞吸积盘的截断的影响

天文学报 2008年第3期49卷 243-250页

作者：牛强中国科学院国家天文台/云南天文台昆明650011

采用吸积盘-冕模型研究了粘滞对黑洞X射线双星和低光度活动星系核(LLAGN)中吸积盘的截断以及黑洞X射线双星中高低态转变的影响.以前的分析表明,冕的结构对粘滞的大小非常敏感.因此详细计算了一系列粘滞系数情况下冕的结构.为了便于与观... 详细信息

采用吸积盘-冕模型研究了粘滞对黑洞X射线双星和低光度活动星系核(LLAGN)中吸积盘的截断以及黑洞X射线双星中高低态转变的影响.以前的分析表明,冕的结构对粘滞的大小非常敏感.因此详细计算了一系列粘滞系数情况下冕的结构.为了便于与观测比较,将数值计算结果进行解析拟合得到最大蒸发率和粘滞系数α的关系,M/M_(EDD)≈1.08α^(3.35);截断半径和粘滞系数的关系,R/R_s≈36.11α^(-1.94)这些结果可以用来解释光谱态的高低态的转换和截断半径的变化.并将这些结果应用到几个黑洞X射线双星XTE J1118 +480,GX 339—4,以及活动星系核NGC 4636中.

关键词：物理数据与过程黑洞物理,吸积吸积盘,X-射线双星

Magnetic and Velocity Fields in Flare Regions

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天文研究与技术 1999年第S1期 175-181页

作者： li Wei 1(Beijing astronomical {2., The chinese academy of sciences, Beijing 100012.china) 2.national astronomical Observatories, The chinese academy of sciences, Beijing 100012. china)

This paper reviews observations of the solar magnetic and velocity fields in active regions where flares produce. Our study includes (1) the relationship among the magnetic fields, Doppler velocity fields and flares; (2. the relationship between magnetic shear and flares; (3) the relationship among electric currents, electric helicity and flares; (4) the evidence for non-potential magnetic field.

关键词： Magnetic and Velocity Fields in Flare Regions

Orbit determination for geostationary satellites with the combination of transfer ranging and pseudorange data

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1746-1754页

作者： GUO Rui1,2.3,4,HU XiaoGong2.4,liU li1,WU Xiaoli1,HUANG Yong2.4 & HE Feng1 1 Beijing Global Information Application and Development Center,Beijing 100094,china 2.Shanghai astronomical observatory,chinese academy of sciences,Shanghai 2.0030,china 3 Graduate University of chinese academy of sciences,Beijing 100049,china 4 Space Navigation and Positioning Technology,Laboratory of Shanghai Municipal,Shanghai 2.0030,china Beijing Global Information Application and Development Center Beijing China Shanghai astronomical observatory Chinese Academy of Sciences Shanghai China Graduate University of chinese academy of sciences Beijing China Space Navigation and Positioning Technology Laboratory of Shanghai Municipal Shanghai China

Geostationary satellites(GEOs) play a significant role in the regional satellite navigation *** experiments show that the clock corrections could be mitigated through a single strategy or double differencing strategies for a navigation constellation,but for the mode of individual GEO orbit determination,high precision orbit and clock correction could not be obtained in the orbit determination based on the pseudorange data.A new GEO combined precise orbit determination(POD) strategy is studied in this paper,which combines pseudorange data and C-band transfer ranging *** strategy overcomes the deficiency of C-band transfer ranging caused by limited stations and tracking time *** the combination of transfer ranging and pseudorange data,clock corrections between the GEO and the stations can be estimated simultaneously along with orbital parameters,maintaining self-consistency between the satellite ephemeris and clock correction *** error covariance analysis is conducted to illuminate the contributions from the transfer ranging data and the psudoranging *** data collected for a chinese GEO satellite with 3 C-band transfer ranging stations and 4 L-band pseudorange tracking stations,POD experiments indicate that a meter-level accuracy is *** root-mean-square(RMS) of the post-fit C-band ranging data is about 0.2.3 m,and the RMS of the post-fit pseudorange is 0.408 *** component errors of the POD experiments are independently evaluated with the satellite laser ranging(SLR) data from a station in Beijing,with the residual RMS of 0.076 *** SLR evaluation also suggests that for 2.h orbital predication,the predicted radial error is about 0.404 m,and the clock correction error is about 1.38 *** for the combination of one C-band transfer ranging station and 4 pseudorange stations,POD is able to achieve a reasonable accuracy with the radial error of 0.2.0 m and the 2.h predicted radial error of 0.888 *** syn

关键词： satellite navigation precise orbit determination pseudorange equipment ranging delay GEO SLR

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

An Interpretation of a Radiation Damage Phenomenon of the Solar-A CCD

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天文研究与技术 1999年第S1期 139-142页

作者： Song Qian, Cao Wenda (yunnan observatory, The {2., kunming 650011, china) (national astronomical Observatories, The {2., Beijing 100012. E mail: qiansong@163. net)

High energy radiation exists in the space natural radiation environment may cause the degradation of the performance of charge coupled devices used in space. The Solar A satellite was launched in 1991. Since then, radiation damage effected phenomena have been reported. The flatband voltage shift resulted from the trapped holes within the insulator layer between the CCD gates and bulk silicon may throw light on the interpretation of some of the radiation damage phenomena.

关键词： An Interpretation of a Radiation Damage SPIE Phenomenon of the Solar-A CCD

Adaptive Optics System and Its Application Predictions at 1.2. Telescope of yunnan {2.

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天文研究与技术 1999年第S1期 63-67页

作者： Xiong Yaoheng, Jiang Chongguo, Wang Wu, Zheng Xianming, Zhang Yuncheng, Feng Hesheng (yunnan observatory, {2. astronomical Observatories, The chinese academy of sciences, kunming 650011,china)

A 61 element adaptive optical system has been preliminary tested in the Coudé path of the 1 2. telescope at the yunnan {2. this year. The whole system will be fully operated next year. This paper describes th... 详细信息

关键词： at 1.2. Telescope of Adaptive Optics System and Its Application Predictions yunnan observatory