REDUCING SYSTEMATIC ERROR IN WEAK LENSING CLUSTER SURVEYS
نویسندگان
چکیده
منابع مشابه
Cluster detection in weak lensing surveys
We present an efficient and robust approach for extracting clusters of galaxies from weak lensing survey data and measuring their properties. We use simple, physically-motivated cluster models appropriate for such sparse, noisy data, and incorporate our knowledge of the cluster mass function to optimise the detection of low-mass objects. Despite the method’s non-linear nature, we are able to se...
متن کاملMining Weak Lensing Surveys
We present a survey of the cosmological applications of the next generation of weak lensing surveys, paying special attention to the computational challenges presented by the number of galaxies, N gal ∼ 10 5. We focus on optimal methods with no pixelization and derive a multigrid P 3 M algorithm that performs the relevant computations in O(N gal log N gal) time. We test the algorithm by studyin...
متن کاملPSF Anisotropy and Systematic Errors in Weak Lensing Surveys
Given the basic parameters of a cosmic shear weak lensing survey, how well can systematic errors due to anisotropy in the point spread function (PSF) be corrected? The largest source of error in this correction to date has been the interpolation of the PSF to the locations of the galaxies. To address this error, we separate the PSF patterns into components that recur in multiple exposures/point...
متن کاملCosmology with weak lensing surveys.
Weak gravitational lensing is responsible for the shearing and magnification of the images of high-redshift sources due to the presence of intervening mass. Since the lensing effects arise from deflections of the light rays due to fluctuations of the gravitational potential, they can be directly related to the underlying density field of the large-scale structures. Weak gravitational surveys ar...
متن کاملBackground sky obscuration by cluster galaxies as a source of systematic error for weak lensing
Lensing magnification and stacked shear measurements of galaxy clusters rely on measuring the density of background galaxies behind the clusters. The most common ways of measuring this quantity ignore the fact that some fraction of the sky is obscured by the cluster galaxies themselves, reducing the area in which background galaxies can be observed. We discuss the size of this effect in the Slo...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2014
ISSN: 0004-637X,1538-4357
DOI: 10.1088/0004-637x/786/2/93