Identifying Galactic Halo Substructure in 6D Phase Space Using similar to 13,000 LAMOST K Giants

doi:10.3847/1538-4357/ab2462

CORC > 国家天文台 > 中国科学院国家天文台

	Identifying Galactic Halo Substructure in 6D Phase Space Using similar to 13,000 LAMOST K Giants
	Yang, Chengqun 1,2; Xue, Xiang-Xiang 1; Li, Jing 3,4; Zhang, Lan 1; Liu, Chao 1,2; Zhao, Gang 1,2; Chang, Jiang 1; Tian, Hao 1; Li, Chengdong 1,2
刊名	ASTROPHYSICAL JOURNAL
	2019-07-20
卷号	880 期号:1 页码:15
关键词	Galaxy: evolution Galaxy: formation Galaxy: halo Galaxy: kinematics and dynamics
ISSN号	0004-637X
DOI	10.3847/1538-4357/ab2462
英文摘要	We construct a large halo K-giant sample by combining the positions, distances, radial velocities, and metallicities of over 13,000 LAMOST DR5 halo K giants with the Gaia DR2 proper motions, which covers a Galactocentric distance range of 5-120 kpc. Using a position-velocity clustering estimator (the 6Distance), we statistically quantify the presence of position-velocity substructure at high significance: K giants have more close pairs in position-velocity space than a smooth stellar halo. We find that the amount of substructure in the halo increases with increasing distance and metallicity. With a percolation algorithm named friends-of-friends to identify groups, we identify members belonging to Sagittarius (Sgr) Streams, Monoceros Ring, Virgo Overdensity, Hercules-Aquila Cloud, Orphan Streams, and other unknown substructures and find that the Sgr streams account for a large part of grouped stars beyond 20 kpc and enhance the increase of substructure with distance and metallicity. For the first time, we identify spectroscopic members of Monoceros Ring in the southern and northern Galactic hemispheres, which presents a rotation of about 185 km s(-1) and a mean metallicity of -0.66 dex.
资助项目	National Natural Science Foundation of China[11873052] ; National Natural Science Foundation of China[11890694] ; National Natural Science Foundation of China[11573032] ; National Natural Science Foundation of China[11773033] ; NSFC[11703019] ; NSFC[11703038] ; NSFC[11333003] ; NSFC[11390372] ; National Development and Reform Commission
WOS关键词	DIGITAL SKY SURVEY ; SAGITTARIUS DWARF GALAXY ; LARGE-SCALE STRUCTURE ; MILKY-WAY ; STELLAR HALO ; CANIS MAJOR ; STREAM ; KINEMATICS ; ACCRETION ; STARS
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	IOP PUBLISHING LTD
WOS记录号	WOS:000477645800010
资助机构	National Natural Science Foundation of China ; National Natural Science Foundation of China ; NSFC ; NSFC ; National Development and Reform Commission ; National Development and Reform Commission ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; NSFC ; NSFC ; National Development and Reform Commission ; National Development and Reform Commission ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; NSFC ; NSFC ; National Development and Reform Commission ; National Development and Reform Commission ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; NSFC ; NSFC ; National Development and Reform Commission ; National Development and Reform Commission
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/27184]
专题	中国科学院国家天文台
通讯作者	Yang, Chengqun
作者单位	1.Chinese Acad Sci, Natl Astron Observ, 20A Datun Rd, Beijing 100101, Peoples R China 2.Univ Chinese Acad Sci, Sch Astron & Space Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China 3.China West Normal Univ, Phys & Space Sci Coll, 1 ShiDa Rd, Nanchong 637002, Peoples R China 4.Chinese Acad Sci, SHAO, Nandan Rd, Shanghai 200030, Peoples R China
推荐引用方式 GB/T 7714	Yang, Chengqun,Xue, Xiang-Xiang,Li, Jing,et al. Identifying Galactic Halo Substructure in 6D Phase Space Using similar to 13,000 LAMOST K Giants[J]. ASTROPHYSICAL JOURNAL,2019,880(1):15.
APA	Yang, Chengqun.,Xue, Xiang-Xiang.,Li, Jing.,Zhang, Lan.,Liu, Chao.,...&Li, Chengdong.(2019).Identifying Galactic Halo Substructure in 6D Phase Space Using similar to 13,000 LAMOST K Giants.ASTROPHYSICAL JOURNAL,880(1),15.
MLA	Yang, Chengqun,et al."Identifying Galactic Halo Substructure in 6D Phase Space Using similar to 13,000 LAMOST K Giants".ASTROPHYSICAL JOURNAL 880.1(2019):15.