NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. II. NEUTRAL MAGNESIUM

	NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. II. NEUTRAL MAGNESIUM
	Zhang, Junbo1,2 ; Shi, Jianrong1,2 ; Pan, Kaike 3,4; Prieto, Carlos Allende 5,6; Liu, Chao1
刊名	ASTROPHYSICAL JOURNAL
	2017-01-20
卷号	835 期号:1
关键词	line: formation line: profiles stars: abundances stars: atmospheres
英文摘要	Aiming at testing the validity of our magnesium atomic model and investigating the effects of non-local thermodynamical equilibrium (NLTE) on the formation of the H-band neutral magnesium lines, we derive the differential Mg abundances from selected transitions for 13 stars either adopting or relaxing the assumption of local thermodynamical equilibrium (LTE). Our analysis is based on high-resolution and high signal-to-noise ratio H-band spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) and optical spectra from several instruments. The absolute differences between the Mg abundances derived from the two wavelength bands are always less than 0.1 dex in the NLTE analysis, while they are slightly larger for the LTE case. This suggests that our Mg atomic model is appropriate for investigating the NLTE formation of the H-band Mg lines. The NLTE corrections for the Mg I H-band lines are sensitive to the surface gravity, becoming larger for smaller log g values, and strong lines are more susceptible to departures from LTE. For cool giants, NLTE corrections tend to be negative, and for the strong line at 15765 angstrom they reach -0.14 dex in our sample, and up to -0.22 dex for other APOGEE stars. Our results suggest that it is important to include NLTE corrections in determining Mg abundances from the H-band Mg I transitions, especially when strong lines are used.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	METAL-POOR STARS ; MULTILEVEL RADIATIVE-TRANSFER ; GALACTIC EVOLUTION EXPERIMENT ; LAMBDA ITERATION METHOD ; RED SUPERGIANT STARS ; NON-LTE ANALYSIS ; SDSS-III ; MODEL ATMOSPHERES ; SOLAR ATMOSPHERE ; MILKY-WAY
收录类别	SCI
语种	英语
WOS记录号	WOS:000393455400090
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/8279]
专题	国家天文台_光学天文研究部
作者单位	1.Chinese Acad Sci, Natl Astron Observ, Key Lab Opt Astron, A20 Datun Rd, Beijing 100012, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China 3.Apache Point Observ, POB 59, Sunspot, NM 88349 USA 4.New Mexico State Univ, POB 59, Sunspot, NM 88349 USA 5.Inst Astrofis Canarias, E-38205 Tenerife, Spain 6.Univ La Laguna, Dept Astrofis, E-38206 Tenerife, Spain
推荐引用方式 GB/T 7714	Zhang, Junbo,Shi, Jianrong,Pan, Kaike,et al. NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. II. NEUTRAL MAGNESIUM[J]. ASTROPHYSICAL JOURNAL,2017,835(1).
APA	Zhang, Junbo,Shi, Jianrong,Pan, Kaike,Prieto, Carlos Allende,&Liu, Chao.(2017).NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. II. NEUTRAL MAGNESIUM.ASTROPHYSICAL JOURNAL,835(1).
MLA	Zhang, Junbo,et al."NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. II. NEUTRAL MAGNESIUM".ASTROPHYSICAL JOURNAL 835.1(2017).