Designing weak lensing surveys: a generalized eigenmode analysis
نویسندگان
چکیده
منابع مشابه
Designing Weak Lensing Surveys: A Generalised Eigenmode Analysis
We study the estimators of various second-order weak lensing statistics such as the shear correlation functions ξ± and the aperture mass dispersion 〈M 2 ap〉 which can directly be constructed from weak lensing shear maps. We compare the efficiency with which these estimators can be used to constrain cosmological parameters. To this end we introduce the Karhunen-Loève (KL) eigenmode analysis tech...
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 کاملPrincipal Component Analysis of Weak Lensing Surveys
Aims. We study degeneracies between cosmological parameters and measurement errors from cosmic shear surveys. We simulate realistic survey topologies with non-uniform sky coverage, and quantify the effect of survey geometry, depth and noise from intrinsic galaxy ellipticities on the parameter errors. This analysis allows us to optimise the survey geometry. Methods. We carry out a principal comp...
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 کاملPrincipal Component Analysis of PSF Variation in Weak Lensing Surveys
We introduce a new algorithm for interpolating measurements of the point-spread function (PSF) using stars from many exposures. The principal components of the variation in the PSF pattern from multiple exposures are used to solve for better fits for each individual exposure. These improved fits are then used to correct the weak lensing shapes. Since we expect some degree of correlation in the ...
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: Monthly Notices of the Royal Astronomical Society
سال: 2006
ISSN: 0035-8711,1365-2966
DOI: 10.1111/j.1365-2966.2005.09857.x