The numerical study on the interplay between jets from active galactic nuclei and the multiphase intracluster medium

The feedback from active galactic nuclei (AGN) plays a crucial role in regulating the (thermo)-dynamics of the intracluster medium (ICM). Through spectroscopic analysis, we may constrain the amount of turbulent pressure and heating generated by the AGN cycle. Extended warm ionized and molecular gas structures have been observed in the cluster centers. Their origin is still puzzling, and the role of AGN feedback in producing them is debated. In this Thesis, I performed hydrodynamic simulations with ENZO and AREPO, modelling the evolution of a Perseus-like galaxy cluster, subject to a self-regulated AGN jet feedback. I studied the turbulent motions created by different types of AGN feedback and predicted the observable signatures by analyzing different feedback modes. By following different gas phases, I studied the complex interplay between the AGN activity and the multi-phase medium. My analysis revealed that the gas velocity dispersion correlates in time with the AGN activity. Different feedback modalities produce the observed velocity dispersion while leading to distinct velocity dispersion profiles. I found a correlation between the AGN activity and the steepening of the velocity structure function. I found that during the individual AGN jet bursts, hot material, injected laterally to the jet axis, compresses the hot ICM, leading to the formation of cold clumps on a timescale of ∼ 30 Myr. The condensation is highly promoted once the local turbulent Mach number in the hot gas component takes values around ∼ 0.3. This line of research will allow us to use detections of gas turbulent motions detectable by XRISM  to better constrain the duty cycle and energetics of AGN feedback in galaxy clusters. The process for cold gas condensation is a further step in understanding which kind of fluid perturbations promote the formation of a cold component in cluster cores.