Understanding Shape and Centroid Deviations in 39 Strong Lensing Galaxy Clusters in Various Dynamical States

Raven Gassis; Matthew B. Bayliss; Keren Sharon; Guillaume Mahler; Michael D. Gladders; Håkon Dahle; Michael K. Florian; Jane R. Rigby; Michael McDonald; Lauren Elicker; M. Riley Owens

arXiv · 2310.18250

Understanding Shape and Centroid Deviations in 39 Strong Lensing Galaxy Clusters in Various Dynamical States

Raven Gassis·Matthew B. Bayliss·Keren Sharon·Guillaume Mahler·Michael D. Gladders·Håkon Dahle·Michael K. Florian·Jane R. Rigby·Michael McDonald·Lauren Elicker·M. Riley Owens

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Abstract

Through observational tests of strong lensing galaxy clusters, we can test simulation derived structure predictions that follow from $\Lambda$ Cold Dark Matter ($\Lambda$CDM) cosmology. The shape and centroid deviations between the total matter distribution, stellar matter distributions, and hot intracluster gas distribution serve as an observational test of these theoretical structure predictions. We measure the position angles, ellipticities, and locations/centroids of the brightest cluster galaxy (BCG), intracluster light (ICL), the hot intracluster medium (ICM), and the core lensing mass for a sample of strong lensing galaxy clusters from the SDSS Giant Arcs Survey (SGAS). We utilize HST WFC3/IR imaging data to measure the shapes/centroids of the ICL and BCG distributions and use Chandra ACIS-I X-ray data to measure the shapes/centroids of ICM. Additionally, we measure the concentration parameter c and asymmetry parameter A to incorporate cluster dynamical state into our analysis. Using this multicomponent approach, we attempt to constrain the astrophysics of our strong lensing cluster sample and evaluate the different components in terms of their ability to trace out the DM halo of clusters in various dynamical states.

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Raven Gassis, Matthew B. Bayliss, Keren Sharon, Guillaume Mahler, Michael D. Gladders, Håkon Dahle, Michael K. Florian, Jane R. Rigby, Michael McDonald, Lauren Elicker, M. Riley Owens. 2023-10-27. Understanding Shape and Centroid Deviations in 39 Strong Lensing Galaxy Clusters in Various Dynamical States. https://arxiv.org/abs/2310.18250

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