The large-scale structure of the Universe at redshift z ~ 2 is undergoing a transition from the most overdense protoclusters to massive, virialized halos on a timescale of ~1 Gyr. Studying the properties of these structures is key to understanding the evolution of galaxies, the origin and evolution of the hot, diffuse intracluster medium (ICM), and the highly energetic processes shaping star formation and nuclear activity in protocluster member galaxies. X-ray observations provide a unique window into these environments, enabling the study of obscured nuclear activity, diffuse inverse Compton emission from radio jets, and thermal emission from the (proto-)ICM. In this framework, we present detailed studies of clusters and protoclusters with XMM-Newton and Chandra to provide estimates of the feedback energy budget, test for the presence of cool cores and cooling flows, identify the triggering mechanisms of nuclear activity, and ultimately constrain the baryon cycle in protocluster and young cluster environments, showing how recurrent extreme phenomena have profound implications for the formation and evolution of massive galaxies during this transitional epoch. These observational results will also provide a benchmark for next-generation hydrodynamical simulations and synthetic observations in the context of NewAthena, enabling direct comparisons between the predicted thermodynamic and chemical properties of the forming ICM and the emerging observational picture of large-scale structure assembly at high redshift.
Contact Local: Thierry FOGLIZZO
Organisation: Jérôme Guilet