Speaker
Description
Galaxy clusters are the rarest and largest gravitationally bound structures in the Universe. They are sensitive tracers of the structure on the largest scales and provide constraints on fundamental physics and cosmology. Clusters are, additionally, ideal cosmic laboratories that can be used to explore the effects of, and coupling between, a diverse range of astrophysical feedback processes. Due to the highly nonlinear, vastly multi-scale nature of the problem, numerical simulations have become an invaluable tool for interpreting observational data and exploring the complex interplay between these different processes in a fully cosmological environment.
In this talk I will present new, high-resolution cosmological zoom-in simulations of galaxy clusters which were performed as part of the PICO galaxy cluster project. The simulations I will present here employ models for the acceleration and transport of cosmic ray protons and for anisotropic thermal conduction - processes that are likely highly relevant but whose modelling is often neglected or oversimplified in current high-resolution cosmological cluster simulations. In the talk I will use these simulations to explore the ways in which cosmic ray feedback affects the (micro-)physical properties of the intracluster medium (ICM) and potentially the evolution of clusters themselves. I will examine how their influence evolves with cosmic time and discuss the extent to which these results depend on numerical and physical modelling assumptions. With the aid of these simulations I will additionally explore the impact of weak collisionality on the dynamics and properties of the ICM and highlight observational manifestations.
Simulations such as these will play a crucial role in interpreting the wealth of observational data expected over the coming decades from the next generation of X-ray and radio observatories and enable in-depth studies into the relative importance and effects of feedback processes on the evolution and properties of galaxy clusters.
