A proper-motion membership study of the old open cluster NGC 188

	A proper-motion membership study of the old open cluster NGC 188
	Dinescu, DI ; Girard, TM ; vanAltena, WF ; Yang, TG ; Lee, YW
刊名	ASTRONOMICAL JOURNAL
	1996-03-01
卷号	111 期号:3 页码:1205-1219
ISSN号	0004-6256
英文摘要	Relative proper motions have been determined for 1127 stars in the field of the open cluster NGC 188 from plates spanning a 60-year interval, taken with the 76-cm Thaw refractor of the Allegheny Observatory. Special attention has been paid to the corrections for systematic errors as a function of magnitude and color, and to the treatment of membership probabilities for stars with different proper-motion errors. The study is complete to a magnitude B=16.2. Also some stars brighter than B=12.5 were eliminated from the study because of the large uncertainty in estimating the magnitude equation at the bright end. The final relative proper motions have an accuracy of 0.5 mas/yr for well-exposed stars. From the cluster membership probabilities based on proper motions we obtain 360 cluster members, enabling us to better define the color-magnitude diagram. We provide a list of highly probable candidate blue stragglers in addition to the sample proposed by Eggen & Sandage (1969). In order to investigate mass segregation, we have analyzed the spatial distribution of the possible blue stragglers. Based on our proper-motion probabilities the spatial cumulative distributions show that the blue stragglers are not more centrally concentrated than the red giants. (C) 1996 American Astronomical Society.
WOS关键词	CONTACT BINARIES ; NGC-188 ; M67 ; STARS ; METALLICITIES ; PHOTOMETRY ; VELOCITIES ; ORIGIN ; DISK ; AGE
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	AMER INST PHYSICS
WOS记录号	WOS:A1996TX87900021
内容类型	期刊论文
源URL	[http://210.72.145.45/handle/361003/10939]
专题	中国科学院国家授时中心
通讯作者	Dinescu, DI
作者单位	1.SHAANXI OBSERV,XIAN,PEOPLES R CHINA 2.YONSEI UNIV OBSERV,SEOUL 120749,SOUTH KOREA
推荐引用方式 GB/T 7714	Dinescu, DI,Girard, TM,vanAltena, WF,et al. A proper-motion membership study of the old open cluster NGC 188[J]. ASTRONOMICAL JOURNAL,1996,111(3):1205-1219.
APA	Dinescu, DI,Girard, TM,vanAltena, WF,Yang, TG,&Lee, YW.(1996).A proper-motion membership study of the old open cluster NGC 188.ASTRONOMICAL JOURNAL,111(3),1205-1219.
MLA	Dinescu, DI,et al."A proper-motion membership study of the old open cluster NGC 188".ASTRONOMICAL JOURNAL 111.3(1996):1205-1219.