Soft X-ray emissions of SiIX in Procyon

	Soft X-ray emissions of SiIX in Procyon
	Liang, Guiyun; Zhao, Gang
刊名	NEW ASTRONOMY
	2007-08-01
卷号	12 期号:6 页码:435-440
关键词	Stars : late-type Stars : coronae X-rays : stars
英文摘要	A detailed analysis of emission lines of carbon-like silicon reveals that some ratios of n = 3 -> 2 line intensities are sensitive to the electron density, n, The ratio between two groups of 3d -> 2p transition lines of 55.246 angstrom and 55.346 angstrom provides a good diagnostic of n, because of the combined characteristic of sensitivity to electron density and relative insensitivity to temperature. From this ratio, a lower limit of the electron density of 0.6 x 10(8) cm(-3) was set for Procyon, which is consistent with the values constrained by C V and Si X emission lines. Significant discrepancies were found between theoretical predictions and observations for the 3s -> 2p lines relative to 3d -> 42p lines in Procyon, recently measured using the Chandra high-resolution transmission grating instrument. The difference of more than a factor of 3, cannot be explained by uncertainties of atomic data. Ness and co-workers also suggested that the effect of opacity appeared not to be a major factor for the discrepancy. For the 3s -> 2p line at 61.611 angstrom, present work indicates that the large discrepancy may be from the contamination of a S VIII line at 61.645 angstrom. For lines at 61.702 and 61.846 angstrom, we suggest that the discrepancies may be attributed to contaminations by currently yet-unknown spectral lines. (C) 2007 Elsevier B.V. All rights reserved.
收录类别	SCI
语种	英语
WOS记录号	WOS:000246728100001
内容类型	期刊论文
源URL	[http://ir.bao.ac.cn/handle/114a11/7191]
专题	国家天文台_光学天文研究部
作者单位	Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China
推荐引用方式 GB/T 7714	Liang, Guiyun,Zhao, Gang. Soft X-ray emissions of SiIX in Procyon[J]. NEW ASTRONOMY,2007,12(6):435-440.
APA	Liang, Guiyun,&Zhao, Gang.(2007).Soft X-ray emissions of SiIX in Procyon.NEW ASTRONOMY,12(6),435-440.
MLA	Liang, Guiyun,et al."Soft X-ray emissions of SiIX in Procyon".NEW ASTRONOMY 12.6(2007):435-440.