Measuring Turbulence in the Circum-Galactic and Intra-Cluster Medium with MUSE Observations

Turbulence crucially impacts many processes related to galaxy evolution, including particle acceleration, magnetic field amplification, and the energy deposition of feedback from stars and black holes. The circum-galactic medium and the intra-cluster medium, which fill the majority of the volume around galaxies and galaxy clusters, are composed of hot plasma that is challenging to observe due to its diffuse nature and the limited resolution of X-ray telescopes. Over the past few years, my group has developed a novel method to measure turbulence in the hot plasma using cool clouds as kinematic tracers. These cool clouds can be observed by MUSE with very high spatial and spectral resolutions, capabilities that surpass those of current and even proposed X-ray telescopes. Initially, we applied this method to the centers of galaxy clusters to probe the effects of supermassive black hole feedback. Subsequent studies by my group and others include turbulence in quasar host nebulae, the tails of jellyfish galaxies moving through galaxy clusters, and high-redshift Lyman α nebulae, all using MUSE observations. These investigations have provided invaluable insights into fundamental processes governing galaxy evolution, such as mergers and black hole feedback. MUSE observations in some environments also allow us to probe plasma kinematics below the electron mean free path, unveiling the complex properties of plasma with unprecedented detail due to microscopic plasma instabilities.