Speaker: Dr. Uri Keshet, CfA
Title: DYNAMICAL AND NONTHERMAL PROCESSES IN GALAXY CLUSTERS
Abstract:
Recent observations of galaxy clusters reveal new insights into the dynamical and nonthermal processes in the intracluster medium (ICM). Tangential discontinuities (known as cold fronts) are directly seen in high resolution X-ray maps. They reveal bulk spiral flows in cluster cores, which magnetize the plasma, give rise to radio minihalos, and may resolve the cooling problem. A combination of strong collisionless shocks that accelerate particles to high energies, and weak shocks that magnetize the plasma, produce a variety of radio phenomena, and gamma-ray virial rings which should be identified in the 5-year Fermi data. �