31颗射电星的位置和自行

在１９８５年至１９８８年间，用佘山４０ｃｍ天体照相仪进行了射电星观测，得出３１颗射电星在ＦＫ５系统中的位置和自行，并将所得的自行值和ＰＰＭ及ＣＡＭＣ星表中的相应结果作了比较。     

射电星的光学位置和自行

1980－1981年期间，上海天台Ⅱ型光电等高仪和丹容等高仪（OPL No.14）共观测了15颗射电星。在FK5星表系统中得到了这些射电星的位置，并由这些观测位置与它们在其他星表例如G C，CAMC和W5／50中的相应位置进行比较，求得了这些射电星的自行。把我们求得的这些射电星的自行和PPM及CAMC星表中的相应自行作了比较，相互符合很一致。     

射电星自行

由佘山40厘米天体照相仪的观测，求得射电星（UV PSC，RU CNC，AD LEO，CYG x-1,RT LAC和DM＋542486）在AGK3系统中的自行。并和其他观测结果作了比较。     

FK5系统中60颗射电星自行

本利用较长时间段的两期照相观测资料，对60颗射电星进行坐标系统和参考星表的系统统一后，求得它们在FK5系统部自行，这些射电星的平均自行精度在赤经和赤纬方向上分别为±0″.0043/yr和±0″.0042/yr，比原来SAO星表的自行精度±0″.0119／yr和±0″.0113yr高2.7倍左右。     

27颗射电星的自行结果

由上海天台的射电星观测，以及其他仪器的射电星观测结果，求得16颗射电星在FK5系统中的自行，同时将以前发现过的部分射电星的自行，利用相应的昨系统差，亦统一化算到FK5系统，得到了27颗射电星的自行结果。     

观测射电星联系依巴谷星表和地面光学星表自行的精度估计

用蒙特卡罗方法对佘山40厘米望远镜射电星的观测模拟，由照相测定的自行来估计依巴谷星表和光学星表自行间联系的精度。结果表明由90颗星估计的联系精度为0″.16／百年。     

射电星光学和射电位置的初步比较

利用30颗左右射电星的光学和射电位置，在坐标和自行系统、参考星表及位置历元统一的基础上，得到了光学系统与射电系统间的转动参数的初步结果。     

由光电等高仪1型在伊尔库茨克观测得到的22颗射电星的光学位置

根据原中国科学院陕西天文台 (CSAO) (现已更名为中国科学院国家授时中心 )与俄罗斯东西伯利亚物理技术和无线电测量研究所 (VSNIIFTRI)之间签定的科学合作协议 ,陕西天文台光电等高仪 1型在伊尔库茨克进行了为期近 5年的星表观测。根据这些高精度的观测资料共编算出包括 81 7颗星的无赤纬盲区的等高仪星表 (其中首批 2 0 0颗已在欧洲《Astronomy&Astrophysics》上发表 )和 2 2颗射电星的光学位置表 ,后者在本文中给出。此外 ,这几年的测时测纬资料还同时发往莫斯科 ,参加俄罗斯的地球定向参数 (EOP—earthorientationparameters)服务系统     

对太阳Ⅰ型源自行的观测和讨论

我们使用密云“4×16”复合干涉仪跟踪观测太阳(中天前后各三小时),以确定Ⅰ型源的二维位置并分析它的自行。 460 MHz Ⅰ型源通常位于相应黑子群的径向延长线上,偏差不超过0′.5。 我们发现,多数Ⅰ型源不时处于缓慢运动之中,速率为10~5—10~6厘米/秒。凡有自行的Ⅰ型源对应的活动区具有较剧烈的耀斑活动。而无自行的Ⅰ型源对应的活动区,在以源存在日为中心,前后各一天(共三天)内,不出现一级以上耀斑。 我们认为,Ⅰ型源的自行,反映了磁力线管的运动,磁场位形的变化。而这种变化可能与耀斑活动有关。     

Measuring the Distance of VX Sagittarii with SiO Maser Proper Motions

We report on 43GHz v=1, J=1-0 SiO maser proper motions in the circumstellar envelope of the M-type semi-regular variable star VX Sgr, observed by Very Long Baseline Array (VLBA) at 3 epochs during 1999 April-May. Applying the statistical parallax analysis to these proper motions, we estimated a distance of VX Sgr of 1.57±0.27kpc, which is consistent with that based on the proper motions of H2O masers, or on the assumption that VX Sgr belongs to the Sgr OB1 association. At this distance, VX Sgr can be classified as a red supergiant. Comparing the statistical parallax method with those of model fitting and annual parallax, we think that the statistical parallax method may be a good way of estimating SiO maser distances at present.     

四颗射电源在依巴谷和PPM星表中的光学定位

利用北京天文台施密特望远镜的CCD巡天资料（BATC）中的20次观测,用IRAF软件处理得到星象中心位置,以依巴谷星表和PPM星表作为参考星表,用底片常数法进行处理,得到4颗河外射电源0851 202,1228 126,1442 101,1749 701的光学位置。文中还对所得到的位置与射电位置作了比较。     

射电源0716 714和0839 187的光学定位

利用北京天文台具有ＣＣＤ终端的６０ｃｍ光学望远镜（Ｖ波段）观测射电源的光学对应体，得到了０７１６＋７１４和０８３９＋１８７精确的光学位置。参考星表采用拉帕尔玛（ＬａＰａｌｍａ）的１８ｃｍ全自动子午环观测资料编制的ＣＡＭＣ星表，该星表是ＦＫ５星表系统。两颗源位置的内符精度约为０．″１９，与其他作者给出的光学和射电位置观测结果分别进行了比较     

Common Proper Motion Search for Faint Companions Around Early-Type Field Stars – Progress Report

The multiplicity of early-type stars is still not well established. The derived binary fraction is different for individual star forming regions, suggesting a connection with the age and the environment conditions. The few studies that have investigated this connection do not provide conclusive results. To fill in this gap, we started the first detailed adaptive-optic-assisted imaging survey of early-type field stars to derive their multiplicity in a homogeneous way. The sample has been extracted from the Hipparcos Catalog and consists of 341 BA-type stars within ∼300 pc from the Sun. We report the current status of the survey and describe a Monte-Carlo simulation that estimates the completeness of our companion detection.     

Determination of the Proper Motions and Membership of the Globular Cluster M3 and of its Orbit in the Galaxy

We examine 14 plates of the globular cluster M3 (NGC 5272) taken with the 40 cm refractor at the Sheshan station of Shanghai Astronomical Observatory. The plates span over a period of about 77 years. The positions and absolute proper motions of eight stars in the Hipparcos Catalogue and of 49 stars in the Tycho-2 Catalogue are used as the reference frame. The astrometric reduction is made with the central overlapping principle. The absolute proper motions of 534 stars in a region of about 100' × 100' around the cluster are measured. With the new proper motion data the membership probabilities of the stars are determined. The average absolute proper motion obtained for the cluster is -0.06@0.30 mas yr-1 in R.A. and -2.6@0.30 mas yr-1 in Decl. By combining this result with the known distance and radial velocity of the cluster, we also obtained the Galactic orbit of M3 for a chosen three-component Galactic potential.     

恒星射电耀发6cm波段偏振观测试验

利用新疆天文台南山基地25m射电望远镜在6cm波段对恒星V772 Her和βPer进行了偏振观测试验.通过数据处理和校准得到恒星的射电光变曲线.探测到V772 Her的射电耀发现象,耀发时的线偏振度约达30%,偏振位置角约4°;探测到βPer的缓变成份及叠加其上的快速耀发,βPer耀发时线偏振很弱.     

26颗亮射电星的观测结果

本文给出了用云南天文台Ⅱ型光电等高仪从1986年10月至1990年12月观测得到的26颗亮射电星的位置改正。     

Globular Clusters: Absolute Proper Motions and Galactic Orbits

We cross-match objects from several different astronomical catalogs to determine the absolute proper motions of stars within the 30-arcmin radius fields of 115 Milky-Way globular clusters with the accuracy of 1–2 mas yr^?1. The proper motions are based on positional data recovered from the USNO-B1, 2MASS, URAT1, ALLWISE, UCAC5, and Gaia DR1 surveys with up to ten positions spanning an epoch difference of up to about 65 years, and reduced to Gaia DR1 TGAS frame using UCAC5 as the reference catalog. Cluster members are photometrically identified by selecting horizontal- and red-giant branch stars on color–magnitude diagrams, and the mean absolute proper motions of the clusters with a typical formal error of about 0.4 mas yr^?1 are computed by averaging the proper motions of selected members. The inferred absolute proper motions of clusters are combined with available radial-velocity data and heliocentric distance estimates to compute the cluster orbits in terms of the Galactic potential models based on Miyamoto and Nagai disk, Hernquist spheroid, and modified isothermal dark-matter halo (axisymmetric model without a bar) and the same model + rotating Ferre’s bar (non-axisymmetric). Five distant clusters have higher-than-escape velocities, most likely due to large errors of computed transversal velocities, whereas the computed orbits of all other clusters remain bound to the Galaxy. Unlike previously published results, we find the bar to affect substantially the orbits of most of the clusters, even those at large Galactocentric distances, bringing appreciable chaotization, especially in the portions of the orbits close to the Galactic center, and stretching out the orbits of some of the thick-disk clusters.