Weak lensing reconstruction through cosmic magnification - II. Improved power spectrum determination and map-making

	Weak lensing reconstruction through cosmic magnification - II. Improved power spectrum determination and map-making
	Yang, Xinjuan 1,2; Zhang, Pengjie 2,3; Zhang, Jun 3; Yu, Yu2
刊名	MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
	2015-02-11
卷号	447 期号:1 页码:345-362
关键词	gravitational lensing: weak cosmological parameters cosmology: theory dark matter
英文摘要	The existence of galaxy intrinsic clustering severely hampers the weak lensing reconstruction from cosmic magnification. In Paper I, we proposed a minimal variance estimator to overcome this problem. By utilizing the different dependences of cosmic magnification and galaxy intrinsic clustering on galaxy flux, we demonstrated that the otherwise overwhelming galaxy intrinsic clustering can be significantly suppressed such that lensing maps can be reconstructed with promising accuracy. This procedure relies heavily on the accuracy of determining the galaxy bias from the same data. Paper I adopts an iterative approach, which degrades towards high redshift. The current paper presents an alternative method, improving over Paper I. We prove that the measured galaxy clustering between flux bins allows for simultaneous determination of the lensing power spectrum and the flux dependence of galaxy bias, at this redshift bin. Compared to Paper I, the new approach is not only more straightforward but also more robust. It identifies an ambiguity in determining the galaxy bias and further discovers a mathematically robust way to suppress this ambiguity to negligible level (similar to 0.1 per cent). The accurately determined galaxy bias can then be applied to the minimal variance estimator proposed in Paper I to improve the lensing map-making. The gain at high redshift is significant. These maps can be used to measure other statistics, such as cluster finding and peak statistics. Furthermore, by including galaxy clustering measurement between different redshift bins, we can also determine the lensing cross power spectrum between these bins, up to a small and correctable multiplicative factor (similar to 0.2-1 per cent for different redshift bin couples).
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	LYMAN-ALPHA ABSORBERS ; LARGE-SCALE STRUCTURE ; SOUTH-POLE TELESCOPE ; DARK-MATTER HALOS ; QUASAR-GALAXY ; COSMOLOGICAL APPLICATIONS ; MODEL PREDICTIONS ; LEGACY SURVEY ; SHEAR ; MASS
收录类别	SCI
语种	英语
WOS记录号	WOS:000350272700027
公开日期	2015-08-18
内容类型	期刊论文
源URL	[http://119.78.226.72/handle/331011/18211]
专题	上海天文台_星系宇宙学重点实验室
作者单位	1.Zhejiang Univ Technol, Inst Adv Phys & Math, Hangzhou 310032, Zhejiang, Peoples R China 2.Shanghai Astron Observ, Key Lab Res Galaxies & Cosmol, Shanghai 200030, Peoples R China 3.Shanghai Jiao Tong Univ, Dept Phys & Astron, Ctr Astron & Astrophys, Shanghai 200240, Peoples R China
推荐引用方式 GB/T 7714	Yang, Xinjuan,Zhang, Pengjie,Zhang, Jun,et al. Weak lensing reconstruction through cosmic magnification - II. Improved power spectrum determination and map-making[J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,2015,447(1):345-362.
APA	Yang, Xinjuan,Zhang, Pengjie,Zhang, Jun,&Yu, Yu.(2015).Weak lensing reconstruction through cosmic magnification - II. Improved power spectrum determination and map-making.MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY,447(1),345-362.
MLA	Yang, Xinjuan,et al."Weak lensing reconstruction through cosmic magnification - II. Improved power spectrum determination and map-making".MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 447.1(2015):345-362.