2022/01/31 by Shiang-Chih Wang, S.B. Wang, H. -Y. Karen Yang +1
Engineering · Physics and Astronomy · #Aerodynamics and Acoustics in Jet Flows #Astronomy #Astrophysics #Fluid Dynamics and Turbulent Flows #Galaxy #Galaxy cluster #Intracluster medium #Laser-Plasma Interactions and Diagnostics #Physics #astro-ph.HE
paper · pdf · doi:10.1093/mnras/stac788
10 pages, 8 figures, accepted to MNRAS
arxiv created 2022/03/17 · openalex publication_date 2022/03/21 · arxiv updated 2022/03/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT Feedback from active galactic nuclei (AGNs) is believed to be the most promising solution to the cooling flow problem in cool-core clusters. Dissipation of sound waves is considered as one of the possible heating mechanisms; however, its relative contribution to heating remains unclear. To estimate the energy budget for heating, we perform 3D hydrodynamic simulations of AGN jet injections in a Perseus-like cluster and quantify the amount of energy stored in the forms of weak shocks and waves. We find that, for a single jet injection with typical parameters in cool-core clusters, ∼9 \rm per cent of the total jet energy is stored in compressional waves (including both shocks and waves). However, due to the destructive effects among randomly phased waves as well as the dissipation of shock energies, in our simulations including self-regulated AGN feedback, no more than 3 \rm per cent of the total injected energy goes into compressional waves. We further separate the energy contribution from shocks and waves and find that, for a single outburst, the shocks can only contribute to ∼20-30 \rm per cent of the total compressional energy in the inner radii and quickly dissipate away. In the self-regulated case where shocks are repeatedly generated, shocks completely dominate over sound waves in the inner region and can still provide ∼40-50 \rm per cent of the total compressional energy at outer radii. Our results suggest that the production of sound waves is not as efficient as what was previously found, and thus sound wave dissipation may be a subdominant source of heating in cool-core clusters.