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arXiv · 2610.00477

The impact of relativistic AGN jets on realistic galaxy cluster environments

K. Hervella-Seoane·M. Perucho·S. Planelles·J. M. Martí·V. Quilis
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Abstract

Context. Low-power FRI-like radio jets dominate the AGN population, yet the main mechanism of heating the intracluster medium (ICM) and its efficiency remain a matter of debate. Aims. We investigate the impact of intermediate-power FRI-like relativistic jets on the inner region of realistic ICM, focusing on the role of weak shocks on heating and the environmental coupling in regulating energy deposition. Methods. We present six three-dimensional relativistic-hydrodynamic simulations of (1e44 - 1e45) erg/s FRI-like jets propagating through the central regions of realistic ICM environments extracted from cosmological GADGET-3 runs. Each simulation tracks 20 Myr of continuous jet activity with radiative cooling included. Results. Despite their intermediate power and mildly relativistic speed at injection, they decelerate rapidly to trans-sonic velocities (average Mach numbers ~ 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. Conclusions. Our results demonstrate that heating of the intergalactic and intracluster medium is highly efficient even in the case of weak shocks in 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.

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K. Hervella-Seoane, M. Perucho, S. Planelles, J. M. Martí, V. Quilis. 2026-09-30. The impact of relativistic AGN jets on realistic galaxy cluster environments. https://doi.org/10.1051/0004-6361%2F202659737

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