TWO-COMPONENT STRUCTURE OF THE H beta BROAD-LINE REGION IN QUASARS. I. EVIDENCE FROM SPECTRAL PRINCIPAL COMPONENT ANALYSIS
文献类型:期刊论文
作者 | Hu C(胡晨)![]() |
刊名 | ASTROPHYSICAL JOURNAL
![]() |
出版日期 | 2012 |
卷号 | 760期号:2页码:126 |
关键词 | line: profiles methods: data analysis methods: numerical methods: statistical quasars: emission lines quasars: general |
英文摘要 | We report on a spectral principal component analysis (SPCA) of a sample of 816 quasars, selected to have small Fe II velocity shifts with spectral coverage in the rest wavelength range 3500-5500 angstrom. The sample is explicitly designed to mitigate spurious effects on SPCA induced by Fe II velocity shifts. We improve the algorithm of SPCA in the literature and introduce a new quantity, the fractional-contribution spectrum, that effectively identifies the emission features encoded in each eigenspectrum. The first eigenspectrum clearly records the power-law continuum and very broad Balmer emission lines. Narrow emission lines dominate the second eigenspectrum. The third eigenspectrum represents the Fe II emission and a component of the Balmer lines with kinematically similar intermediate-velocity widths. Correlations between the weights of the eigenspectra and parametric measurements of line strength and continuum slope confirm the above interpretation for the eigenspectra. Monte Carlo simulations demonstrate the validity of our method to recognize cross talk in SPCA and firmly rule out a single-component model for broad H beta. We also present the results of SPCA for four other samples that contain quasars in bins of larger Fe II velocity shift; similar eigenspectra are obtained. We propose that the H beta-emitting region has two kinematically distinct components: one with very large velocities whose strength correlates with the continuum shape and another with more modest, intermediate velocities that is closely coupled to the gas that gives rise to Fe II emission. |
学科主题 | Astronomy & Astrophysics |
收录类别 | SCI |
WOS记录号 | WOS:000311217000030 |
公开日期 | 2016-05-03 |
源URL | [http://ir.ihep.ac.cn/handle/311005/224426] ![]() |
专题 | 高能物理研究所_粒子天体物理中心 |
推荐引用方式 GB/T 7714 | Hu C,王建民;Hu, C,Wang, JM,et al. TWO-COMPONENT STRUCTURE OF THE H beta BROAD-LINE REGION IN QUASARS. I. EVIDENCE FROM SPECTRAL PRINCIPAL COMPONENT ANALYSIS[J]. ASTROPHYSICAL JOURNAL,2012,760(2):126. |
APA | 胡晨.,王建民;Hu, C.,Wang, JM.,Ho, LC.,Ferland, GJ.,...&Wang, Y.(2012).TWO-COMPONENT STRUCTURE OF THE H beta BROAD-LINE REGION IN QUASARS. I. EVIDENCE FROM SPECTRAL PRINCIPAL COMPONENT ANALYSIS.ASTROPHYSICAL JOURNAL,760(2),126. |
MLA | 胡晨,et al."TWO-COMPONENT STRUCTURE OF THE H beta BROAD-LINE REGION IN QUASARS. I. EVIDENCE FROM SPECTRAL PRINCIPAL COMPONENT ANALYSIS".ASTROPHYSICAL JOURNAL 760.2(2012):126. |
入库方式: OAI收割
来源:高能物理研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。