SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM

	SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM
	Li, Jing 1,2; Smith, Martin C.1; Zhong, Jing 1; Hou, Jinliang 1; Carlin, Jeffrey L.3; Newberg, Heidi Jo 3; Liu, Chao4 ; Chen, Li 1; Li, Linlin 1; Shao, Zhengyi 1
刊名	ASTROPHYSICAL JOURNAL
	2016-05-20
卷号	823 期号:1
关键词	galaxies: individual (Sagittarius) Galaxy: halo Galaxy: structure stars: abundances stars: distances stars: late-type
英文摘要	Using a spectroscopically confirmed sample of M giants, M dwarfs, and quasars from the LAMOST survey, we assess how well Wide-field Infrared Survey Explorer (WISE) and Two Micron All Sky Survey color cuts can be used to select M giant stars. The WISE bands are very efficient at separating M giants from M dwarfs, and we present a simple classification that can produce a clean and relatively complete sample of M giants. We derive a new photometric relation to estimate the metallicity for M giants, calibrated using data from the APOGEE survey. We find a strong correlation between the (W1-W2) color and [M/H], where almost all of the scatter is due to photometric uncertainties. We show that previous photometric distance relations, which are mostly based on stellar models, may be biased and devise a new empirical distance relation, investigating trends with metallicity and star formation history. Given these relations, we investigate the properties of M giants in the Sagittarius stream. The offset in the orbital plane between the leading and trailing tails is reproduced, and by identifying distant M giants in the direction of the Galactic anticenter, we confirm that the previously detected debris in the outer halo is the apocenter of the trailing tail. We also find tentative evidence supporting an existing overdensity near the leading tail in the northern Galactic hemisphere, possibly an extension to the trailing tail (so-called Branch C). We have measured the metallicity distribution along the stream, finding a clear metallicity offset between the leading and trailing tails, in agreement with models for the stream formation. We include an online table of M giants to facilitate further studies.
收录类别	SCI
语种	英语
WOS记录号	WOS:000377216300059
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/5343]
专题	国家天文台_光学天文研究部
作者单位	1.Chinese Acad Sci, Shanghai Astron Observ, Key Lab Galaxies & Cosmol, 80 Nandan Rd, Shanghai 200030, Peoples R China 2.Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China 3.Rensselaer Polytech Inst, Dept Phys Appl Phys & Astron, Troy, NY 12180 USA 4.Chinese Acad Sci, Natl Astron Observ, Key Lab Opt Astron, Datun Rd 20A, Beijing 100012, Peoples R China 5.Univ Groningen, Kapteyn Astron Inst, POB 800, NL-9700 AV Groningen, Netherlands
推荐引用方式 GB/T 7714	Li, Jing,Smith, Martin C.,Zhong, Jing,et al. SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM[J]. ASTROPHYSICAL JOURNAL,2016,823(1).
APA	Li, Jing.,Smith, Martin C..,Zhong, Jing.,Hou, Jinliang.,Carlin, Jeffrey L..,...&Tian, Hao.(2016).SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM.ASTROPHYSICAL JOURNAL,823(1).
MLA	Li, Jing,et al."SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM".ASTROPHYSICAL JOURNAL 823.1(2016).