1709.09721
Deep lensing with a twist: E and B modes in a field with multiple lenses
Bradshaw, Jee, Tyson
Explore aperture mass mapping of LSS using the E- and B-modes produced in the WL analysis of a field of galaxy clusters in Lynx. Deep multi-color Suprime-cam and HST imaging data are jointly analyzed to produce estimates of the locations and shear of background galaxies, which are then used to infer the locations and masses of foreground over densities (E-modes) through the optimal filtering of axisymmetric tangential shears. By approximating this foreground structure of E-monds as a superposition of NFW-like halos, model the observed ellpiticitiy of each source galaxy as a sum of shears induced by foreground mass structures. Also make maps of the B-modes by similarly filtering the axisymmetric cross shear and show that these B-modes in fact contain information about the cluster masses and locations after identifying several expected sources of B-modes including edge effects, source clustering, and multiple lensing. Verify this reconstruction method using N-body sim data and demonstrate how the observed B-modes naturally occur when background galaxies are sheared through a cosmic web of lenses.
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