Weak lensing magnification reconstruction with the modified internal linear combination method  

作　　者：Shu-Tong Hou Yu Yu Peng-Jie Zhang 侯书通;余瑜;张鹏杰(Department of Astronomy,School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Key Laboratory for Particle Physics and Cosmology,Shanghai Jiao Tong University,Shanghai 200240,China;Tsung-Dao Lee Institute,Shanghai 200240,China)

机构地区：[1]Department of Astronomy,School of Physics and Astronomy,Shanghai Jiao Tong University,Shanghai 200240,China [2]Shanghai Key Laboratory for Particle Physics and Cosmology,Shanghai Jiao Tong University,Shanghai 200240,China [3]Tsung-Dao Lee Institute,Shanghai 200240,China

出　　处：《Research in Astronomy and Astrophysics》2021年第10期51-60,共10页天文和天体物理学研究（英文版）

基　　金：supported by the National Key Basic Research and Development Program of China(No.2018YFA0404504);the National Natural Science Foundation of China(Grant Nos.11773048,11621303 and 11890691);the science research grants from the China Manned Space Project(No.CMS-CSST-2021B01);the“111”Project of the Ministry of Education(Grant No.B20019)。

摘　　要：Measuring weak lensing cosmic magnification signal is very challenging due to the overwhelming intrinsic clustering in the observed galaxy distribution.In this paper,we modify the Internal Linear Combination(ILC)method to reconstruct the lensing signal with an extra constraint to suppress the intrinsic clustering.To quantify the performance,we construct a realistic galaxy catalogue for the LSST-like photometric survey,covering 20000 deg^(2) with mean source redshift at z_(s)~1.We find that the reconstruction performance depends on the width of the photo-z bin we choose.Due to the correlation between the lensing signal and the source galaxy distribution,the derived signal has smaller systematic bias but larger statistical uncertainty for a narrower photo-z bin.We conclude that the lensing signal reconstruction with the Modified ILC method is unbiased with a statistical uncertainty <5% for bin width Δz^(P)=0.2.

关 键 词：cosmology:observations large-scale structure of universe weak lensing 

分 类 号：P159[天文地球—天文学]