Strongly lensed cluster substructures are not in tension with ?CDM

ABSTRACT Strong gravitational lensing observations can test structure formation models by constraining the masses and concentrations of subhaloes in massive galaxy clusters. Recent work has concluded that cluster are more abundant and/or concentrated than predicted ? cold dark matter (?CDM) simulations; this finding been interpreted as arising from unidentified issues with simulations or an incorrect understanding nature matter. We these hypotheses comparing observed subhalo maximum circular velocities vmax to predictions high-resolution Hydrangea simulation suite, which is based on successful EAGLE model. Above ${\sim}10^{11}\, \mathrm{M}_\odot$, simulated mass distribution mass–vmax relation agrees well observations, due presence baryons during tidal stripping. Similar agreement found for lower resolution IllustrisTNG300 simulation. In combination, our results suggest abundance concentration substructures not tension ?CDM, but may provide useful constraints refinement baryon physics simulations.