3D Asymmetrical motions of the Galactic outer disc with LAMOST K giant stars

doi:10.1093/mnras/sty739

CORC > 国家天文台 > 中国科学院国家天文台

	3D Asymmetrical motions of the Galactic outer disc with LAMOST K giant stars
	Wang, Haifeng 1,2; Lopez-Corredoira, Martin 3,4; Carlin, Jeffrey L.5; Deng, Licai 1,2
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2018-07-01
卷号	477 期号:3 页码:2858-2866
关键词	Galaxy: disc Galaxy: kinematics and dynamics Galaxy: structure
ISSN号	0035-8711
DOI	10.1093/mnras/sty739
英文摘要	We present a three dimensional velocity analysis of Milky Way disc kinematics using LAMOST K giant stars and the GPS1 proper motion catalogue. We find that Galactic disc stars near the anticentre direction (in the range of Galactocentric distance between R = 8 and 13 kpc and vertical position between Z=-2 and 2 kpc) exhibit asymmetrical motions in the Galactocentric radial, azimuthal, and vertical components. Radial motions are not zero, thus departing from circularity in the orbits; they increase outwards within R less than or similar to 12 kpc, show some oscillation in the northern (0< Z < 2 kpc) stars, and have north-south asymmetry in the region corresponding to a well-known nearby northern structure in the velocity field. There is a clear vertical gradient in azimuthal velocity, and also an asymmetry that shifts from a larger azimuthal velocity above the plane near the solar radius to faster rotation below the plane at radii of 11-12 kpc. Stars both above and below the plane at R greater than or similar to 9 kpc exhibit net upward vertical motions. We discuss some possible mechanisms that might create the asymmetrical motions, such as external perturbations due to dwarf galaxy minor mergers or dark matter sub-haloes, warp dynamics, internal processes due to spiral arms or the Galactic bar, and (most likely) a combination of some or all of these components.
资助项目	National Key Research and Development Program of China[2017YFA0402702] ; Spanish Ministry of Economy and Competitiveness[AYA2015-66506-P] ; National Development and Reform Commission
WOS关键词	STELLAR VELOCITY DISTRIBUTION ; SKY SURVEY 2MASS ; MILKY-WAY DISC ; SOLAR NEIGHBORHOOD ; SPIRAL ARMS ; MINOR MERGERS ; DENSITY WAVES ; DARK-MATTER ; LOCAL DISC ; BAR
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	OXFORD UNIV PRESS
WOS记录号	WOS:000433893700002
资助机构	National Key Research and Development Program of China ; National Key Research and Development Program of China ; Spanish Ministry of Economy and Competitiveness ; Spanish Ministry of Economy and Competitiveness ; National Development and Reform Commission ; National Development and Reform Commission ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Spanish Ministry of Economy and Competitiveness ; Spanish Ministry of Economy and Competitiveness ; National Development and Reform Commission ; National Development and Reform Commission ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Spanish Ministry of Economy and Competitiveness ; Spanish Ministry of Economy and Competitiveness ; National Development and Reform Commission ; National Development and Reform Commission ; National Key Research and Development Program of China ; National Key Research and Development Program of China ; Spanish Ministry of Economy and Competitiveness ; Spanish Ministry of Economy and Competitiveness ; 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/114a11/21666]
专题	中国科学院国家天文台
通讯作者	Wang, Haifeng
作者单位	1.Chinese Acad Sci, Natl Astron Observ, Key Lab Opt Astron, Beijing 100012, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Inst Astrofis Canarias, E-38205 Tenerife, Spain 4.Univ La Laguna, Dept Astrofis, E-38206 Tenerife, Spain 5.LSST, 950 North Cherry Ave, Tucson, AZ 85719 USA
推荐引用方式 GB/T 7714	Wang, Haifeng,Lopez-Corredoira, Martin,Carlin, Jeffrey L.,et al. 3D Asymmetrical motions of the Galactic outer disc with LAMOST K giant stars[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2018,477(3):2858-2866.
APA	Wang, Haifeng,Lopez-Corredoira, Martin,Carlin, Jeffrey L.,&Deng, Licai.(2018).3D Asymmetrical motions of the Galactic outer disc with LAMOST K giant stars.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,477(3),2858-2866.
MLA	Wang, Haifeng,et al."3D Asymmetrical motions of the Galactic outer disc with LAMOST K giant stars".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 477.3(2018):2858-2866.