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卫星圆轨道假设对GPS无线电掩星反演地球大气参数的影响

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天文学报 2001年第3期42卷 243-247页

作者：蒋虎中国科学院上海天文台上海200030

给出GPS无线电掩星反演地球大气参数过程中计算大气折射角的解析表达式 .以圆轨道假设下的大气折射角计算值为先验约束 ,采用迭代法对不引入圆轨道假设情况的大气折射角进行归算 ,在此基础 ,利用反演方法得到了引入和不引入圆轨道假定... 详细信息

给出GPS无线电掩星反演地球大气参数过程中计算大气折射角的解析表达式 .以圆轨道假设下的大气折射角计算值为先验约束 ,采用迭代法对不引入圆轨道假设情况的大气折射角进行归算 ,在此基础 ,利用反演方法得到了引入和不引入圆轨道假定两种情况下大气参数 (气压和温度 )的差分序列 .结果表明 :卫星圆轨道假设对GPS无线电掩星反演大气参数的影响 ,在气压方面为 1mbar左右 ,而在气温方面为 1°K左右 .这一结果支持了目前无线电掩星定性误差估计研究中通常引入卫星圆轨道假设这个近似处理方法的合理性 ;同时也表明 :若在高精度反演地球大气参数时。

关键词：全球定位系统无线电掩星地球大气参数卫星圆轨道假设 GPS 大气折射角

拱星OH脉泽辐射频谱的双峰结构和多重分离的膨胀拱星壳

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天文学报 1998年第3期39卷 237-243页

作者：俞志尧中国科学院上海天文台上海200030

对一些OH／IR星的拱星OH脉泽的观测结果表明，在双峰结构谱线轮廓上常常可以发现一些小峰叠加在双峰上，即在谱线轮廓的双峰结构中的每个峰是由几个小峰叠加而成的．从脉泽的辐射转移方程和拱星包层的速度结构出发，研究拱星OH脉泽辐射... 详细信息

对一些OH／IR星的拱星OH脉泽的观测结果表明，在双峰结构谱线轮廓上常常可以发现一些小峰叠加在双峰上，即在谱线轮廓的双峰结构中的每个峰是由几个小峰叠加而成的．从脉泽的辐射转移方程和拱星包层的速度结构出发，研究拱星OH脉泽辐射频谱的轮廓特征，提出多重分离的膨胀拱星亮模型，很好地解释了双峰结构的奇特观测现象．

关键词：拱星 OH脉泽辐射双峰结构膨胀拱星壳

ASTROMETRIC OBSERVATIONS AFTER 1988.0

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中国科学院上海天文台年刊 1994年 45-48页

作者： Li Zhengxin(shanghai observatory,{2. )

After the closing of the BIH at 1988. 0, 64-42.optical astrometric instrumcnts over the world were still operated in the past four years. A brief presentation of its situation since 1988. O is described, including the number of instruments operated, the numbor of mcasurements made,avorage precision of a group measurement and BRP obtained. A short discussion is also given.

关键词：地球自转参数纬度测量天文学 ERP 时间测量

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 20003.)

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

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

EVIDENCE OF PLUMB LINE VARIATIONS IN EUROPE FROM LATITUDE OBSERVATIONS

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中国科学院上海天文台年刊 1995年 41-48页

作者： Li Zhengxin Qiah Changxia(shanghai observatory,{2.)

In response to the resolutions of the IUGG-IAG and IAU in 1991, a study of thepossibility of deriving long-term variations of bldnib line from Optical astrometric latitudedata has been carried out. Evidence of the exi... 详细信息

关键词：纬度变化天文观测重力场变化长期变化

Optical observations of Scorpius X-1 in 2.08:Evidence of rapid variability

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 143-146页

作者： CAO XiaoFeng1,2.YU WenFei1,YAN Zhen1 & SUN Li1 1 shanghai astronomical {2.,shanghai 20003.,china 2.Institute of Astrophysics,Huazhong Normal University,Wuhan 430079,china shanghai astronomical {2. Shanghai China Institute of Astrophysics Huazhong Normal University Wuhan China

Optical observations of Sco X-1 with exposure times around 0.5 s were performed with the 1.56 m telescope of the shanghai astronomical {2. in *** these observations,we studied the fluctuation of the optical flux on three short timescales(5,10,100 s).We found that the standard deviations of fluctuations on these three timescales differ from those of Gaussian distributions by 7 Sigma,5 Sigma and 3 Sigma,*** result suggests that the variations in the intensity on these short timescales differ from pure statistical fluctuations,which,we suggest,is due to the intrinsic variability in the optical emission.

关键词： accretion disks stars:individual(Scorpius X-1) optical:stars

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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

The Channel Maps and the Position-Velocity Diagrams of Multi-core Structure of Cepheus C

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天文研究与技术 1999年第S1期 218-221页

作者： Yu Zhi yao 1,2., Jiang Dong rong 1,2.1 (shanghai astronomical {2., The chinese academy of sciences, shanghai 20003., china) 2.(National astronomical Observatories, The chinese academy of sciences, china E mail: zyyu@center. shao. ac.

The first important problem in the star forming process is the formation of proto star core in star forming regions of molecular cloud. The multi core structure in star forming regions is related to the forming of proto star core. The molecular radiation of C 18 O( J = 1-0) in Cepheus C has been observed. The C 18 O( J = 1-0) observations form the basis for an interesting study on the cloud cores and star formation activity in the cores of the Cepheus C. In order to study the multi core structure of C 18 O( J = 1-0) in the Cepheus C the channel maps and the position velocity diagrams of C 18 O( J = 1-0) will be shown. From the maps it is found that the contour level and distribution size of the three cores in Cepheus C are related to the channel velocity very much. The channel velocity of C 18 O( J = 1-0) molecules in core b, which distributed in all the channels velocity, is different with one in core a and core c very much. The C 18 O( J = 1-0) molecules in core a and core c of the Cepheus C mostly distributed in the blue shifted channel velocity relating to peak velocity, and only in -10.0 ～ -9.5 km/s, which is the red shifted channel velocity relating to peak velocity. And the contour level of C 18 O( J = 1-0) in -10.0 ～ -9.5 km/s is small and the distrbution size in the channel map is small. According to the position velocity diagrams the asymmetry of the distribution both blue shifted and red shifted components should reflect the asymmetry of the profile. From the diagrams it also is found that the contour level and the distribution size of the three cores are different from each other. Both results from the maps and diagrams are coincident with each other.

关键词： Maps The Channel Maps and the Position-Velocity core Diagrams of Multi-core Structure of Cepheus C