Power spectrum and intermittency of Ly alpha transmitted flux of QSO HE 2347-4342

CORC > 紫金山天文台 > 中国科学院紫金山天文台 > 宇宙伽马暴、中子星及相关物理研究团组

	Power spectrum and intermittency of Ly alpha transmitted flux of QSO HE 2347-4342
	Jamkhedkar, P ; Feng, LL; Zheng, W ; Fang, LZ
刊名	ASTROPHYSICAL JOURNAL
	2005-11-01
卷号	633 期号:1 页码:52-60
关键词	cosmology : theory large-scale structure of universe
ISSN号	0004-637X
英文摘要	We have studied the power spectrum and the intermittent behavior of the fluctuations in the transmitted flux of HE 2347-4342 Ly alpha absorption in order to investigate if there is any discrepancy between the Lambda CDM model with parameters given by the WMAP and observations on small scales. If the non-Gaussianity of the cosmic mass field is assumed to come only from halos with a universal mass profile of the Lambda CDM model, the non-Gaussian behavior of mass field would be effectively measured by its intermittency, because intermittency is a basic statistical feature of the cuspy structures. We have shown that the Ly alpha transmitted flux field of HE 2347-4342 is significantly intermittent on small scales. With the hydrodynamic simulation, we demonstrate that the Lambda CDM model is successful in explaining the power spectrum and intermittency of Ly alpha transmitted flux. Using statistics ranging from second to eighth order, we find no discrepancy between the Lambda CDM model and the observed transmitted flux field and no evidence to support the necessity of reducing the power of density perturbations relative to the standard Lambda CDM model up to comoving scales as small as about 0.08 h(-1) Mpc. Moreover, our simulation samples show that the intermittency exponent of the Ly alpha transmitted flux field is probably scale-dependent. This result is different from the prediction of a universal mass profile with a constant power index of the central cusp. The scale dependence of the intermittency exponent indicates that the distribution of baryonic gas is decoupled from the underlying dark matter.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	COLD DARK-MATTER ; ESSENTIALLY NONOSCILLATORY SCHEMES ; SURFACE BRIGHTNESS GALAXIES ; QSO ABSORPTION-SPECTRA ; INTERGALACTIC MEDIUM ; DENSITY PROFILE ; BARYONIC GAS ; FOREST ; MASS ; HALO
收录类别	SCI
语种	英语
WOS记录号	WOS:000232832500006
公开日期	2012-03-07
内容类型	期刊论文
源URL	[http://159.226.72.40/handle/332002/4180]
专题	紫金山天文台_宇宙伽马暴、中子星及相关物理研究团组
作者单位	1.Univ Arizona, Dept Phys, Tucson, AZ 85721 USA 2.Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China 3.Chinese Acad Sci, Purple Mt Observ, Nanjing 210008, Peoples R China 4.Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA
推荐引用方式 GB/T 7714	Jamkhedkar, P,Feng, LL,Zheng, W,et al. Power spectrum and intermittency of Ly alpha transmitted flux of QSO HE 2347-4342[J]. ASTROPHYSICAL JOURNAL,2005,633(1):52-60.
APA	Jamkhedkar, P,Feng, LL,Zheng, W,&Fang, LZ.(2005).Power spectrum and intermittency of Ly alpha transmitted flux of QSO HE 2347-4342.ASTROPHYSICAL JOURNAL,633(1),52-60.
MLA	Jamkhedkar, P,et al."Power spectrum and intermittency of Ly alpha transmitted flux of QSO HE 2347-4342".ASTROPHYSICAL JOURNAL 633.1(2005):52-60.