Oral Presentation

Multi-probe mass models of massive galaxy clusters

Author(s): Benjamin Beauchesne (Durham University)

Presenter: Benjamin Beauchesne (University of Durham)

Galaxy clusters are the greatest structures bound by gravity in the cosmos. Such massive objects bend the light from background objects, allowing us to study their mass contents with the gravitational lensing effect. In the context of the standard cosmological model, their contents are largely dominated by dark matter (DM) and are thus a unique laboratory for studying its properties.
Recent studies have shown that it was possible to make a self-consistent mass distribution model separating the intra-cluster gas from the rest of the mass to benefit from X-ray constraints (Beauchesne et al., 2024). Thanks to the ability of new observing facilities to map the ICL in a fraction of the observing time previously required, this allows us to include it in galaxy cluster mass models. Hence, it is now possible to fully disentangle the DM mass distribution from its baryonic counterpart at the cluster scale by extending the method with mass probes targeting that component.
I will present a modified version of the method presented in Beauchesne et al. (2024), where we include a new mass component to reproduce the ICL. We extend the set of observables by adding direct constraints on the velocity dispersions for the cluster member, the brightest cluster galaxy and the ICL. The produced models can be split into each main cluster component, and each baryon component is fitted on specific observables jointly with the lensing. I will present the early results obtained on the cluster test case, Abell S1063.