On the impact of weak shocks driven by intermediate-power AGN jets on galaxy clusters

Low-power radio jets dominate the AGN population, yet their main feedback mechanism and efficiency remains mysterious. In this talk, we will present our recent work focus on the impact of intermediate-power relativistic jets on the inner region of realistic intracluster mediums (ICM), focusing on the role of weak shocks on heating and the environmental coupling in regulating energy deposition. We present six three-dimensional relativistic-hydrodynamic (RHD) jet simulations with powers between Lj ∼ 10^44–10^45 erg/s, propagating through realistic ICM extracted from cosmological Gadget-3 runs. Each simulation tracks 20 Myr of continuous jet activity with radiative cooling included. Despite their intermediate power and midly relativistic speed at injection, these jets decelerate rapidly to trans-sonic velocities (average Mach 2.3) and generate weak bow shocks that dominate the energy transfer. Approximately, 80% of the injected kinetic power is converted into internal energy of the ambient ICM, and bremsstrahlung cooling noticeably reduces the temperature of the shocked shells as they expand. Our results demonstrate that heating of the intergalactic and intracluster medium is highly efficient even in the case of weak shocks in low power and/or FRI-like sources. This finding suggests low-power jets are a viable solution to the long-standing cooling-flow problem and likely regulate star formation across diverse galaxy cluster environments.