Galaxy clusters at radio wavelengths: Are strong lenses overconcentrated? And other cosmological questions

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Strong lensing galaxy clusters provide promising probes of cosmological structure formation. Strong lensing halos can be identified in cosmological simulations through ray tracing techniques and their properties measured. Previous studies have found some evidence that strong lensing clusters are more concentrated than expected, with possible explanations including baryonic effects or more exotic physics such as early dark energy. Using Sunyaev-Zeldovich (SZ) observations to measure the mass on large scales and strong lensing mass modeling for small scales, we find that the clusters are more concentrated than expected at the 97% confidence level. We also investigate the placement of lensed images with respect to the SZ gas and Brightest Cluster Galaxy orientations. I will also discuss the redshift evolution of radio Active Galactic Nuclei in clusters, which is relevant for determining cosmological parameters from SZ surveys as well as for understanding the energy budgets in cluster cores.