Institute for Advanced Study Informal Astrophysics Seminar

Galaxy clusters are the largest dark matter-dominated objects in the Universe with the most massive baryonic component in the form of hot, X-ray-emitting plasma. Due to their size and relative simplicity, clusters are unique laboratories for probing plasma properties on microscales, such as turbulence, viscosity, heat conduction, magnetic fields. These properties remain largely unmeasured and their theoretical predictions vary by orders of magnitude. In my talk, I will discuss how statistical properties of gas perturbations imprinted in the high-resolution X-ray images of galaxy clusters are used to probe gas turbulence, the effective equation of state of small-scale perturbations and plasma behavior on spatial scales comparable to Coulomb mean free path. The latter allows us to probe transport processes, in particular, gas viscosity in the bulk intergalactic plasma. At the end of my talk, I will briefly discuss how we will measure the statistical properties of the gas velocity field with the near-future XRISM mission.