The Strongest Cluster Lenses: An Analysis of the Relation Between Strong Gravitational Lensing Strength and the Physical Properties of Galaxy Clusters

TL;DR

This study analyzes the relationship between galaxy cluster properties and their gravitational lensing strength using multiple models, revealing that the inner mass density slope and extent of lensing evidence are key indicators of lensing power.

Contribution

It introduces a comprehensive analysis linking inner mass profile features to lensing strength, aiding in the design of more effective future lensing observations.

Findings

Inner mass density slope correlates with lensing strength.

Large Einstein area indicates stronger lensing.

Extended lensing evidence suggests higher lensing power.

Abstract

Strong gravitational lensing provides unique opportunities to investigate the mass distribution at the cores of galaxy clusters and to study high redshift galaxies. Using $94$ strong lensing models of $74$ cluster fields from the \textit{Hubble} Frontier Fields (HFF), Reionization Lensing Cluster Survey (RELICS), and Sloan Giant Arcs Survey (SGAS), modeled with three parametric approaches, we evaluate the lensing strength of each cluster (area with $|\mu|\geq3$ for $z_s=9$). We assess how large scale mass, projected inner core mass, and the inner slope of the projected mass density profile relate to lensing strength. While we do not identify a strong correlation between lensing strength and large scale mass, we reveal that the inner slope ($50$ kpc~$\leq r \leq~200$ kpc) of the projected mass density profile is indicative of lensing strength and can set an upper bound on the possible lensing strength of a cluster. We find that the effective Einstein area correlates with lensing strength, and that a large ($\gtrsim 30^{''}0$) radial extent of lensing evidence is a strong indicator of a powerful lens. These results can help to more efficiently design future observations to maximize lensing strength.