This repository contains the data and code to reproduce the results in Sparse Reconstruction of the Merging A520 Cluster System (Peel et al. 2017). It relies on the multi-scale sparsity-based mass mapping software called Glimpse. We have reconstructed the mass distribution of Abell 520, a merging galaxy cluster system also known as the 'cosmic train wreck'. We obtained high-resolution mass maps using two separate galaxy catalogs derived from HST observations and compared the results to previous weak-lensing studies of the system.
Galaxy shear catalogues for A520 from two different telescope surveys are available. The first is from Clowe et al. 2012, ApJ 758, 128 (C12), and the second is from Jee et al. 2014, ApJ 783, 78 (J14).
The Glimpse software is required to reproduce our mass maps. Details of the algorithm and tests on simulated data can be found in High resolution weak lensing mass mapping combining shear and flexion (Lanusse et al. 2016).
$ cd data
$ glimpse config_A520_c12.ini A520_cat_c12.fits kappa.fits
Mass maps reconstructed with Glimpse on C12 (left) and J14 (right) telescope data. The projected matter distributions (dark + luminous) are in color and overlaid on the science image.
Source galaxy density maps from C12 (left) and J14 (right) data sets. The C12 galaxy ellipticity catalog was derived from a combination of Magellan and HST/ACS images with galaxy number densities of 22 and 56 per square arcmin, respectively. The J14 catalog comes from the same ACS data as C12 but has a higher galaxy number density of 109 per square arcmin due to a different reduction pipeline.