NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. I. NEUTRAL SILICON

	NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. I. NEUTRAL SILICON
	Zhang, Junbo1,2 ; Hi, Jianrong1,2 ; Pan, Kaike 3,4; Allende Prieto, Carlos 5,6; Liu, Chao1
刊名	ASTROPHYSICAL JOURNAL
	2016-12-20
卷号	833 期号:2
关键词	line: formation line: profiles stars: abundances stars: atmospheres
英文摘要	We investigated the reliability of our silicon atomic model and the influence of non-local thermodynamical equilibrium (NLTE) on the formation of neutral silicon (Si I) lines in the near-infrared (near-IR) H-band. We derived the differential Si abundances for 13 sample stars with high-resolution H-band spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE), as well as from optical spectra, both under local thermodynamical equilibrium (LTE) and NLTE conditions. We found that the differences between the Si abundances derived from the H-band and from optical lines for the same stars are less than 0.1 dex when the NLTE effects are included, and that NLTE reduces the line-to-line scatter in the H-band spectra for most sample stars. These results suggest that our Si atomic model is appropriate for studying the formation of H-band Si lines. Our calculations show that the NLTE corrections of the Si I H-band lines are negative, i.e., the final Si abundances will be overestimated in LTE. The corrections for strong lines depend on surface gravity, and tend to be larger for giants, reaching similar to-0.2 dex in our sample, and up to similar to-0.4 dex in extreme cases of APOGEE targets. Thus, the NLTE effects should be included in deriving silicon abundances from H-band Si I lines, especially for the cases where only strong lines are available.
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	MULTILEVEL RADIATIVE-TRANSFER ; GALACTIC EVOLUTION EXPERIMENT ; LAMBDA ITERATION METHOD ; LATE-TYPE STARS ; OSCILLATOR-STRENGTHS ; MILKY-WAY ; SDSS-III ; NON-LTE ; FE-I ; TRANSITION-PROBABILITIES
收录类别	SCI
语种	英语
WOS记录号	WOS:000391169600012
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/6804]
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, Sch Astron & Space 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,Hi, Jianrong,Pan, Kaike,et al. NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. I. NEUTRAL SILICON[J]. ASTROPHYSICAL JOURNAL,2016,833(2).
APA	Zhang, Junbo,Hi, Jianrong,Pan, Kaike,Allende Prieto, Carlos,&Liu, Chao.(2016).NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. I. NEUTRAL SILICON.ASTROPHYSICAL JOURNAL,833(2).
MLA	Zhang, Junbo,et al."NLTE ANALYSIS OF HIGH-RESOLUTION H-BAND SPECTRA. I. NEUTRAL SILICON".ASTROPHYSICAL JOURNAL 833.2(2016).