Cluster arc statistics

Abstract

We study the strong gravitational lensing properties of galaxy clusters obtained from N-body simulations with a standard ΛCDM cosmology. We have used the 32 most massive clusters from a simulation at various redshifts and ray-traced through the clusters to investigate giant arc statistics. We have investigated the prevalence of multiple arc systems, finding that almost half of the clusters that produce giant arcs give multiple arcs, which agrees with the RCS ii observations. We have also investigated the mass distributions that are efficient in lensing and the effect of source size on lensing cross section. We find that the latter is important, despite previous claims to the contrary. We also investigate a number of other factors that are important in the formation of giant arcs.