RED RUNAWAYS II: LOW-MASS HILLS STARS IN SDSS STRIPE 82

doi:10.3847/0004-637X/832/1/10

CORC > 上海天文台 > 中国科学院上海天文台

	RED RUNAWAYS II: LOW-MASS HILLS STARS IN SDSS STRIPE 82
	Zhang, Yanqiong 1,4; Smith, Martin C.4; Carlin, Jeffrey L.2,3
刊名	ASTROPHYSICAL JOURNAL
	2016-11-20
卷号	832 期号:1
关键词	Galaxy: Center Galaxy: Kinematics And Dynamics Galaxy: Structure
ISSN号	0004-637X
DOI	10.3847/0004-637X/832/1/10
英文摘要	Stars ejected from the Galactic Center can be used to place important constraints on the Milky Way potential. Since existing hypervelocity stars are too distant to accurately determine orbits, we have conducted a search for nearby candidates using full three-dimensional velocities. Since the efficacy of such studies is often hampered by deficiencies in proper motion catalogs, we have chosen to utilize the reliable, high-precision Sloan Digital Sky Survey (SDSS) Stripe 82 proper motion catalog. Although we do not find any candidates which have velocities in excess of the escape speed, we identify 226 stars on orbits that are consistent with Galactic Center ejection. This number is significantly larger than what we would expect for halo stars on radial orbits and cannot be explained by disk or bulge contamination. If we restrict ourselves to metal-rich stars, we find 29 candidates with [ Fe/H] > 0.8 dex and 10 with [ Fe/H] > 0.6 dex. Their metallicities are more consistent with what we expect for bulge ejecta, and so we believe these candidates are especially deserving of further study. We have supplemented this sample using our own radial velocities, developing an algorithm to use proper motions for optimizing candidate selection. This technique provides considerable improvement on the blind spectroscopic sample of SDSS, being able to identify candidates with an efficiency around 20 times better than a blind search.
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	IOP PUBLISHING LTD
WOS记录号	WOS:000400475800003
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/32595]
专题	中国科学院上海天文台
通讯作者	Zhang, Yanqiong
作者单位	1.Chinese Acad Sci, Grad Univ, 19A Yuquan Rd, Beijing 100049, Peoples R China 2.LSST, 933 North Cherry Ave, Tucson, AZ 85721 USA 3.Rensselaer Polytech Inst, Troy, NY USA 4.Chinese Acad Sci, Shanghai Astron Observ, Key Lab Galaxies & Cosmol, 80 Nandan Rd, Shanghai 200030, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Yanqiong,Smith, Martin C.,Carlin, Jeffrey L.. RED RUNAWAYS II: LOW-MASS HILLS STARS IN SDSS STRIPE 82[J]. ASTROPHYSICAL JOURNAL,2016,832(1).
APA	Zhang, Yanqiong,Smith, Martin C.,&Carlin, Jeffrey L..(2016).RED RUNAWAYS II: LOW-MASS HILLS STARS IN SDSS STRIPE 82.ASTROPHYSICAL JOURNAL,832(1).
MLA	Zhang, Yanqiong,et al."RED RUNAWAYS II: LOW-MASS HILLS STARS IN SDSS STRIPE 82".ASTROPHYSICAL JOURNAL 832.1(2016).