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Ian dell'Antonio

Publications and source records attributed to Ian dell'Antonio.

2 recordsLinked to original sources
arXiv2020

Dark Matter Distribution of Four Low-z Clusters of Galaxies

We present here the weak gravitational lensing detection of four nearby galaxy clusters in the southern sky: Abell 2029, Abell 85, Abell 1606 and Abell 2457. The weak lensing detections of Abell 1606 and Abell 2457 are the first in the literature. This work capitalizes on the wide field of view of the Dark Energy Camera at the Cerro Tololo Inter-American Observatory, which we use to obtain deep, multi-wavelength imaging of all targets. We publish maps of the clusters' projected mass distributions, and obtain the $M_{200}$ of their clusters through NFW profile fits to the two-dimensional tangential ellipticity signal.

astro-ph.CO↗
arXiv2015

Mass Substructure in Abell 3128

We perform a detailed 2-dimensional weak gravitational lensing analysis of the nearby (z = 0.058) galaxy cluster Abell 3128 using deep ugrz imaging from the Dark Energy Camera (DECam). We have designed a pipeline to remove instrumental artifacts from DECam images and stack multiple dithered observations without inducing a spurious ellipticity signal. We develop a new technique to characterize the spatial variation of the PSF which enables us to circularize the field to better than 0.5% and thereby extract the intrinsic galaxy ellipticities. By fitting photometric redshifts to sources in the observation, we are able to select a sample of background galaxies for weak lensing analysis free from low-redshift contaminants. Photometric redshifts are also used to select a high-redshift galaxy subsample with which we successfully isolate the signal from an interloping z = 0.44 cluster. We estimate the total mass of Abell 3128 by fitting the tangential ellipticity of background galaxies with the weak lensing shear profile of an NFW halo, and also perform NFW fits to substructures detected in the 2-D mass maps of the cluster. This study yields one of the highest resolution mass maps of a low-z cluster to date, and is the first step in a larger effort to characterize the redshift evolution of mass substructures in clusters.

astro-ph.CO↗