球状星团M3天区534颗恒星的绝对自行测定

以《Hipparcos星表》体现的国际天球参考架为基础 ,对球状星团M3(NGC 5 2 72 )中心附近 10 0′×10 0′天区内 5 34颗恒星 ,使用上海天文台佘山 4 0cm折射望远镜拍摄的底片资料 ,以 8颗《Hipparcos星表》中恒星和 4 9颗《Tycho - 2星表》中恒星的位置和绝对自行为参考 ,归算得到了位置和绝对自行 ,并估计了成员概率     

疏散星团NGC2244天区恒星的绝对自行研究

利用上海天文台相隔35年的两期照相底片资料,测定了疏散星团NGC2244所在天区55’×55’范围内495颗恒星基于Tycho-2星表的位置和绝对自行,并对自行精度作了初步分析。     

球状星团M79天区169颗恒星的位置和自行归算及其成员概率

使用上海天文台佘山40cm折射望远镜拍摄的底片资料,对球状星团M79中心附近15’×15’天区内106颗恒星和63颗Tycho-2星,以《Tycho-2星表》中M79附近1°×1°天区内上述63颗Ty cho-2星的位置和自行为参考,归算得到了所有169颗恒星的位置和自行,并估计了其成员概率。     

球状星团NGC4147天区115颗恒星的绝对自行和BVRI测光

以上海天台佘山40cm折射望远镜于1958年拍摄的3张照相底片为第一期资料,印度Kavalur的2.34m Vainu Bappu望远镜于1996年用CCD拍摄的4幅图象为第二期资料,使用Brosche等人1985年发表的球状星团NGC4147天区42颗恒星的位置和绝对自行作为参考架,用中心重叠法进行天体测量归算,得到了这个星团中心附近11'×11'天区内到B＝17.6mag为止115颗恒星的位置和绝对自行,并利用这些自行对成员概率作了估计,同时,还用Vainu Bappu望远镜的CCD进行了BVRI四色测光。本给出了这115颗恒星的位置、绝对自行和成员概率数据,同时,还给出了用Vainu Bappu望远镜的CCD获得的这些恒星的BVRI测光数据。     

用佘山40厘米折射望远镜测定的恒星三角视差总览

对于用佘山40厘米折射望远镜拍摄的10组底片，用底片常数法和中心重叠法分别重新作了归算；对于饮食大时角底片的组，归算中使用在恒星常数中加进折射项的办法计入了大气色散改正。给出了15颗星的相对视和自行，以及由重叠解换算的绝对视差，对视差测定值的精度作了讨论。     

球状星团NGC4147的绝对自行和颜色星等图

本文以上海天文台佘山40厘米折射望远镜于1958年拍摄的3张照相底片为第一期,印度Kavalur的234米VainuBappu望远镜于1996年用CCD拍摄的4幅图像为第二期,使用Brosche等1985年发表的球状星团NGC4147天区42颗恒星的位置和绝对自行作为参考架,用中心重叠法进行天体测量归算,得到了这个星团中心附近11'×11'天区内到B＝17.6为止115颗恒星的位置和绝对自行,利用这些自行对成员概率作了估计.本文还给出了用VainuBappu望远镜CCD测光结果得到的这个星因水平文和巨星支恒星V与B-V．V－R和V－I颜色星等图,并对这些颜色星等图和团自行作了讨论,得到这个星团的赤经方向绝对自行为-2.82±0.49mas／yr,赤纬方向绝对自行为2.37±0.43mas／yr.     

疏散星团M11的研究：1.自行测定与成员研究

本文利用中国科学院上海天文台４０厘米双筒天体照相仪所拍摄得的１０对底片（历元差１６─７０年），经ＰＤＳ测量仪测量，共确定了疏散星团Ｍｌｌ天区８７２颗恒星的相对自行，其中８５％以上恒星的自行测定精度好于±０″．１／百年．利用所测得的相对自行和新的数学模型，确定了不同星等组恒星的分布参数并计算了团中心距ｒ≤２５＇内７８５颗恒星的成员概率，其中成员概率大于０．７的恒星共有５４１颗．详细的讨论表明，新方法不仅在理论上更为严格，实用上也是可行的，可以使星团成员确定取得更为合理的结果．     

用照相底片精确测定依巴谷星的自行

利用上海天文台佘山40cm折射望远镜拍摄的历元间隔约为27年的6张底片,共计有14次露光观测,以PPM星表作为初始参考星表,按中心重叠法进行归算,得到了南天区域内21颗恒星的高精度位置和自行,其中有6颗是依巴谷星,它们的赤经和赤纬精度的平均值分别为1.8ms和22mas ,赤经自行和赤纬自行精度的平均值分别灰0.068ms/a和0.97mas/a。     

球状星团M10（NGC6254）的自行研究

利用上海天台和Bonn大学天台的照相底片资料及大视场CCD观测数据,测定了球状星团M10（NGC6254）天台中532颗恒星相对于依巴谷参考系和ACT星表的绝地自行,相对于Hipparcos参考星和ACT参考星分别得到的测定结果符合得很好,根据自行测定结果进行了星团成员判定,有两颗星族II父变星被证实为星团的成员,根据星团的绝对自行,结合其距离与视向速度观测结果,得了了M10的空间运动轨道。     

自行与银河系研究的前沿

简述了精确测定相对自行的方法,特别介绍了在用2～3个历元的底片和CCD观测结果推导恒星自行的过程中如何消除光学视场畸变、星等差和色差的具体办法;并介绍了用星系把相对自行推算绝对自行的方法。还介绍了用自行资料研究银河系结构和演化的一些前沿课题,其中包括星团研究、与银河系兼并的矮星系的发现、暗物质的检测、外星行星的探测和银河系中心黑洞的质量估算等。最后评价了自行在研究银河系中的重要性,论述了我国研制4m光学/近红外望远镜的重要意义。     

Membership and Segregation Effects in the Young Open Cluster NGC 6530

From photographic plate data of Shanghai Astronomical Observatory with a time baseline of 87 years, proper motions and membership probabilities of 364 stars in the open cluster NGC 6530 region are reduced. On the basis of membership determination, luminosity function and segregation effect of the cluster are discussed with details. Spatial mass segregation is obviously present in NGC 6530 while there is no clear evidence for a velocity-mass (or velocity-luminosity) dependence. The observed spatial mass segregation for NGC 6530 might be due to a combination of initial conditions and relaxation process.     

Research on the membership and spatial motion of the open cluster NGC6530

or stars in the region around the open cluster NGC6530, cluster memberships are calculated based on the maximum likelihood principle using proper motions obtained from photographic plates acquired with the 40 cm refraction telescope at Shanghai Astronomical Observatory. Analyses show that the membership determination is very effective with 250 stars having membership probabilities p ≥ 0.9. The spatial motion of the star cluster is also determined and a simple discussion is carried out.     

疏散星团NGC6530的成员研究和空间运动

利用上海天文台40厘米折射望远镜照相观测资料所得出的恒星自行,按最大似然原理确定了疏散星团NGC6530天区内恒星的成员概率．分析表明星团成员确定是非常有效的,成员概率p≥0．9的恒星计有250颗．最后,确定了星团的空间运动,并作了简单的讨论．     

年轻疏散星团NGC 2244的成员概率与空间运动

利用绝对自行资料,确定了年轻疏散星团NGC 2244天区恒星的运动学成员概率,并对星团成员概率以及自行矢量的分布、不同成员概率恒星的位置分布情况、径向数密度轮廓等进行了讨论并给出了星团的特征尺度;进一步结合已知的星团距离和视向速度资料,计算了NGC 2244的三维空间运动速度,结果表明NGC 2244是一个典型的薄盘族星团。     

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.     

Astrometry of the open cluster NGC 2324

New proper motion membership probabilities are given for stars in the region of the cluster NGC 2324. The space density distribution and the luminosity function are discussed. A comparison with previous investigations is presented.     

疏散星团NGC 6530的光度函数和分层效应

该文利用疏散星团NGC 6530的自行观测数据和成员判别结果,给出了星团的光度函数,并详细讨论了星团的质量分层效应。分析表明,NGC 6530存在空间质量分层效应,但并不存在速度质量分层,因此星团的表观空间质量分层可能起因于星团形成时的初始条件,而不是动力学弛豫的结果。     

Measurement of the absolute proper motion of M3 and its space motion

We have measured the absolute proper motions of 534 stars in a 1.5° × 1.5° region around the cluster M3, using 14 plates taken with a 40-cm refractor spanning 80 years. 24 stars in the ACT catalogue were used to define the reference frame and the reduction was made using the central overlapping technique. Using the new data, the membership probabilities were redetermined. The mean absolute motion of the cluster was found to be −0.3 ± 0.3 mas/yr in R.A., and −3.1 ± 0.3 mas/yr in declination. Combining the present data with the known distance and radial velocity, the three-dimensional galactic orbit of M3 was calculated for Allen's galactic potential.     

Astrophysical supplements to the ASCC‐2.5. II. Membership probabilities in 520 Galactic open cluster sky areas

We present a catalogue (CSOCA) of stars residing in 520 Galactic open cluster sky areas which is the result of the kinematic (proper motion) and photometric member selection of stars listed in the homogeneous All‐sky Compiled Catalogue of 2.5Million Stars (ASCC‐2.5).We describe the structure and contents of the catalogue, the selection procedure applied, and the proper motion and photometric membership constraints adopted. In every cluster area the CSOCA contains the complete list of the ASCC‐2.5 stars regardless of their membership probability. For every star the CSOCA includes accurate J2000 equatorial coordinates, proper motions in the Hipparcos system, BV photometric data in the Johnson system, proper motion and photometric membership probabilities, as well as angular distances from the cluster centers for about 166 000 ASCC‐2.5 stars. If available, trigonometric parallaxes, spectral types, multiplicity and variability flags from the ASCC‐2.5, and radial velocities with their errors from the Catalogue of Radial Velocities of Galactic Stars with high precision Astrometric Data (CRVAD) are also given. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)