Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks

doi:10.3847/1538-4357/aa88c7

	Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks
	Shen, Juntai 3,4; Nidever, David L.17; Schultheis, M.18; Roman-Lopes, A.19; Villanova, S.7; Tang, Baitian 7; Geisler, Doug 7; Lin, Chien-Cheng 3,12; Majewski, Steven R.6; Fernandez-Trincado, J. G.7
刊名	ASTROPHYSICAL JOURNAL
	2017-09-20
卷号	847 期号:1
关键词	Galaxy: Abundances Galaxy: Bulge Galaxy: Kinematics And Dynamics Galaxy: Structure
DOI	10.3847/1538-4357/aa88c7
文献子类	Article
英文摘要	A cold, high-velocity (HV, similar to 200 km s(-1)) peak was first reported in several Galactic bulge fields based on the Apache Point Observatory Galaxy Evolution Experiment (APOGEE) commissioning observations. Both the existence and the nature of the HV peak are still under debate. Here we revisit this feature with the latest APOGEE DR13 data. We find that most of the low-latitude bulge fields display a skewed Gaussian distribution with an HV shoulder. However, only 3 out of 53 fields show distinct HV peaks around 200 km s(-1). The velocity distribution can be well described by Gauss-Hermite polynomials, except for the three fields showing clear HV peaks. We find that the correlation between the skewness parameter (h(3)) and the mean velocity ((nu) over bar), instead of a distinctive HV peak, is a strong indicator of the bar. It was recently suggested that the HV peak is composed of preferentially young stars. We choose three fields showing clear HV peaks to test this hypothesis using the metallicity, [alpha/M], and [C/N] as age proxies. We find that both young and old stars show HV features. The similarity between the chemical abundances of stars in the HV peaks and the main component indicates that they are not systematically different in terms of chemical abundance or age. In contrast, there are clear differences in chemical space between stars in the Sagittarius dwarf and the bulge stars. The strong HV peaks off-plane are still to be explained properly and could be different in nature.
WOS关键词	SAGITTARIUS DWARF GALAXY ; N-BODY SIMULATIONS ; MILKY-WAY ; LOCAL STANDARD ; GALACTIC BULGE ; SKY SURVEY ; BAR ; EVOLUTION ; NITROGEN ; STELLAR
WOS研究方向	Astronomy & Astrophysics
语种	英语
WOS记录号	WOS:000411520600002
资助机构	973 Program of China(2014CB845700) ; 973 Program of China(2014CB845700) ; National Natural Science Foundation of China(11333003 ; National Natural Science Foundation of China(11333003 ; CASSACA ; CASSACA ; Newton Advanced Fellowship - Royal Society ; Newton Advanced Fellowship - Royal Society ; Newton Fund ; Newton Fund ; CAS/SAFEA ; CAS/SAFEA ; Shanghai Yangfan Research Grant(14YF1407700) ; Shanghai Yangfan Research Grant(14YF1407700) ; LAMOST ; LAMOST ; NSF(AST-1109718 ; NSF(AST-1109718 ; Chilean BASAL Centro de Excelencia en Astrofisica y Tecnologias Afines (CATA)(PFB-06/2007) ; Chilean BASAL Centro de Excelencia en Astrofisica y Tecnologias Afines (CATA)(PFB-06/2007) ; Fondecyt(1170518) ; Fondecyt(1170518) ; Alfred P. Sloan Foundation ; Alfred P. Sloan Foundation ; U.S. Department of Energy Office of Science ; U.S. Department of Energy Office of Science ; University of Utah ; University of Utah ; 11390372 ; 11390372 ; AST-1312863 ; AST-1312863 ; 11322326 ; 11322326 ; AST-1616436) ; AST-1616436) ; 11403072 ; 11403072 ; 11373032) ; 11373032) ; 973 Program of China(2014CB845700) ; 973 Program of China(2014CB845700) ; National Natural Science Foundation of China(11333003 ; National Natural Science Foundation of China(11333003 ; CASSACA ; CASSACA ; Newton Advanced Fellowship - Royal Society ; Newton Advanced Fellowship - Royal Society ; Newton Fund ; Newton Fund ; CAS/SAFEA ; CAS/SAFEA ; Shanghai Yangfan Research Grant(14YF1407700) ; Shanghai Yangfan Research Grant(14YF1407700) ; LAMOST ; LAMOST ; NSF(AST-1109718 ; NSF(AST-1109718 ; Chilean BASAL Centro de Excelencia en Astrofisica y Tecnologias Afines (CATA)(PFB-06/2007) ; Chilean BASAL Centro de Excelencia en Astrofisica y Tecnologias Afines (CATA)(PFB-06/2007) ; Fondecyt(1170518) ; Fondecyt(1170518) ; Alfred P. Sloan Foundation ; Alfred P. Sloan Foundation ; U.S. Department of Energy Office of Science ; U.S. Department of Energy Office of Science ; University of Utah ; University of Utah ; 11390372 ; 11390372 ; AST-1312863 ; AST-1312863 ; 11322326 ; 11322326 ; AST-1616436) ; AST-1616436) ; 11403072 ; 11403072 ; 11373032) ; 11373032)
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/20115]
专题	国家天文台_星系宇宙学研究部
作者单位	1.Tsinghua Univ, Dept Phys, Ctr Astrophys, Beijing 10086, Peoples R China 2.Chinese Acad Sci, Natl Astron Observ, Kay Lab Opt Astron, Beijing 100012, Peoples R China 3.Chinese Acad Sci, Key Lab Res Galaxies & Cosmol, Shanghai Astron Observ, 80 Nandan Rd, Shanghai 200030, Peoples R China 4.Univ Chinese Acad Sci, Coll Astron & Space Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China 5.Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA 6.Univ Virginia, Dept Astron, POB 400325, Charlottesville, VA 22904 USA 7.Univ Concepcion, Dept Astron, Casilla 160-C, Concepcion, Chile 8.Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 USA 9.Univ Manchester, Jodrell Bank Ctr Astrophys, Sch Phys & Astron, Oxford Rd, Manchester M13 9PL, Lancs, England 10.Univ Utah, Dept Phys & Astron, 115 S 1400 E, Salt Lake City, UT 84112 USA
推荐引用方式 GB/T 7714	Shen, Juntai,Nidever, David L.,Schultheis, M.,et al. Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks[J]. ASTROPHYSICAL JOURNAL,2017,847(1).
APA	Shen, Juntai.,Nidever, David L..,Schultheis, M..,Roman-Lopes, A..,Villanova, S..,...&Zhou, Yingying.(2017).Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks.ASTROPHYSICAL JOURNAL,847(1).
MLA	Shen, Juntai,et al."Chemical Abundances and Ages of the Bulge Stars in APOGEE High-velocity Peaks".ASTROPHYSICAL JOURNAL 847.1(2017).