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Re-Discussion on Motion of shanghai VLBI Station Relative to Eurasian Plate From VLBI

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天文研究与技术 1999年第S1期 134-138页

作者： Yang Zhigen, Zhu Wenyao, Xiong Yongqing, Zhang Qiang (shanghai astronomical {2., The chinese academy of sciences, shanghai 200030, china) (National astronomical Observatories, The chinese academy of sciences, Beijing 100012. china)

By using the results of changing rate of the baseline lengths from shanghai VLBI station to 13 international VLBI stations, respectively, the vertical and horizontal velocities of shanghai VLBI station are re estimated by means of the Least Square Fit method based on the international VLBI station velocities of ITRF96, and the Euler vectors of Eurasian tectonic plate of Sillard et al (1998). The results are such the vertical velocity: -1 86±0 84 mm/yr, horizontal velocity and its local azimuth: 14 2.±0 97 mm/yr, E -12. 49±2. 98 S. If the NNR NUVEL 1A model is used instead of the Euler vectors of Sillard et al., the corresponding results are such -1 86±0 84 mm/yr, 10 56±0 96 mm/yr, E -16° 07±4° 06 S. In addition, the corresponding results for the Urumqi VLBI station are also estimated.

关键词： Relative to Eurasian Plate From VLBI Re-Discussion on Motion of shanghai VLBI Station

OBSERVATION OF AN OUTBURST OF COMET HALE-BOPP IN SEPTEMBER 1996

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中国科学院上海天文台年刊 2000年 76-86页

作者： Tao Jun Qian Bochen Gu Minfeng Tang Yuan Song Baojun (shanghai astronomical {2., chinese academy of sciences, shanghai 200030)

The light curve and images of comet Hale-Bopp(C/1995 O1) in Sept. 1996 are studied. It is found that an outburst happened in Sept. 10-11, 1996. The magnitude of the inner coma region increased by 2.1 mag. and 1.4 mag. on these two days, respectively. Two globular ejecta were found near the nucleus of the comet in Sept.10 and 11, 1996. By extropolating backward from the ejecta, it is found that the initial time of the outburst was on Sept. 9, 1996 (9.5±0.2.T). The physical reason for this outburst is still uncertain. The projected radial velocities of ejecta are 12.m/s and 97m/s.

关键词： Comet C/1995 O1 (Hale-Bopp) - light curve - outburst

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 astronomical Observatories/Yunnan observatory,{2. academy of sciences,Kunming 650011,china 2.Key Laboratory for the Structure and Evolution of Celestial Objects,{2. 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{12.,Hefei 2.002.,china 5 Joint Institute of Galaxies and Cosmology,SHAO and USTC,shanghai 200030,china 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 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. keV) 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 correlation timescale of the X-ray flux during the outbursts of soft X-ray transients

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 161-167页

作者： WU YuXiang1,2.YU WenFei1 & LI TiPei2.1 shanghai astronomical {2.,shanghai 100012.china 2.Department of Engineering Physics & Center for Astrophysics,Tsinghua University,Beijing 100084,china shanghai Astron Observ Shanghai 100012 Peoples R China Tsinghua Univ Dept Engn Phys Beijing 100084 Peoples R China Tsinghua Univ Ctr Astrophys Beijing 100084 Peoples R China

Recent studies of black hole and neutron star low mass X-ray binaries(LMXBs) show a positive correlation between the X-ray flux at which the low/hard(LH)-to-high/soft(HS) state transition occurs and the peak flux of the following HS *** analyzing the data from the All Sky Monitor(ASM) onboard the Rossi X-ray Timing Explorer(RXTE),we show that the HS state flux after the source reaches its HS flux peak still correlates with the transition flux during soft X-ray transient(SXT) *** studying large outbursts or flares of GX 339-4,Aql X-1 and 4U 1705-44,we have found that the correlation holds up to 2.0,40,and 50 d after the LH-to-HS state transition,*** time scales correspond to the viscous time scale in a standard accretion disk around a stellar mass black hole or a neutron star at a radius of-104-5 Rg,indicating that the mass accretion rates in the accretion flow either correlate over a large range of radii at a given time or correlate over a long period of time at a given *** the accretion geometry is a two-flow geometry composed of a sub-Keplerian inflow or outflow and a disk flow in the LH state,the disk flow with a radius up to-105 Rg would have contributed to the nearly instantaneous non-thermal radiation directly or indirectly,and therefore affects the time when the state transition occurs.

关键词： accretion disks black hole physics star:individual(Aquila X-1 GX 339-4 4U 1705-44)

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古气候记录指示的天文周期分析

天文学报 2002年第4期43卷 432-442页

作者：顾震年中国科学院上海天文台上海200030

利用西峰市以西16km处的巴家嘴黄土剖面的上新世以来的(6.2.2.5MaB.P.)磁化率和粒度及太平洋深海沉积物资料,用不同的数据分析方法,不仅得到地球轨道主要参数中(对应于偏心率、交角和气候岁差)的 0.1Ma、0.04Ma和0.02.Ma几个天文周期,... 详细信息

利用西峰市以西16km处的巴家嘴黄土剖面的上新世以来的(6.2.2.5MaB.P.)磁化率和粒度及太平洋深海沉积物资料,用不同的数据分析方法,不仅得到地球轨道主要参数中(对应于偏心率、交角和气候岁差)的 0.1Ma、0.04Ma和0.02.Ma几个天文周期,而且还得到了0.2.Ma、0.15Ma、0.08Ma和0.06Ma其他周期,它们都在80％置信度水平以上.此外,通过小波变换表明,所有这些周期呈现出时变特性,随不同的地质年代增强或逐渐消失.这说明古气候的变化受多种古环境的影响所致.近来提出0.1Ma周期变化不但和地球轨道偏心率有关,而且可能和星际尘埃粒子沉降速率和青藏高原的隆升有着密切的关系.因此,地球轨道参数变化影响气候长期变化只是其中一种因素.

关键词：古气候天文周期地球轨道小波变换偏心率星际尘埃

IRAS 10173+082.的翘曲拱核环中的OH超脉泽

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天文学报 2004年第2期45卷 115-119页

作者：俞志尧中国科学院上海天文台

对IRAS 10173+082.的拱核环中的OH超脉泽进行MERLIN§高分辨观测,得到了拱核环为翘曲的证据,同时得到了10个速度通道中OH超脉泽的等强度轮廓线向东西方向延伸的角尺寸与其相应速度通道中峰束流量密度成正相关关系.

关键词：黑洞物理星系拱核环 OH超脉泽相关关系

Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2. QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4, WANG GuangLi1, ZHENG WeiMin1, GUAN Di3, ZHU RenJie1, WANG WeiHua1, ZHANG XiuZhong1, JIANG DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 shanghai astronomical {2., chinese academy of sciences, shanghai 200030, china 2.Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, china 3 Lunar Explorer Engineering General Department, chinese academy of sciences, Beijing 100012. china 4 Beijing Institute of Tracking and Telecommunications Technology, Beijing 100094, china 1. shanghai astronomical {2. Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover