2024/03/05 by Xiaodong Duan, Duan, Xiaodong, Fulai Guo +1
Physics and Astronomy · #Astro and Planetary Science #Solar and Space Plasma Dynamics #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2403.02807
Multi-wavelength observations indicate that the intracluster medium in some galaxy clusters contains cold filaments, while their formation mechanism remains debated. Using hydrodynamic simulations, we show that cold filaments could naturally condense out of hot gaseous wake flows uplifted by the jet-inflated active galactic nucleus (AGN) bubbles. Consistent with observations, the simulated filaments extend to tens of kiloparsecs from the cluster center, with a representative mass of \rm 108- 109 M\odot for a typical AGN outburst energy of 1060~ \rm erg. They show smooth velocity gradients, stretching typically from inner inflows to outer outflows with velocity dispersions of several hundred kilometers per second. The properties of cold filaments are affected substantially by jet properties. Compared to kinetic-energy-dominated jets, thermal-energy-dominated jets are easier to produce long cold filaments with large masses as observed. AGN jets with an early turn-on time, a low jet base, or a very high power tend to overheat the cluster center, and produce short cold filaments that take a relatively long time to condense out.