Place: 4421 Sterling Hall, Coffee and cookies 3:30 pm, Talk begins 3:45PM
Speaker: Tom Jones, University of Minnesota, School of Physics and Astronomy
Abstract: Galaxy clusters, made mostly of dark matter, are the most massive and last structures to form out of cosmic expansion. They grow on timescales of Gyr through accretion and mergers. They are also frequently harassed by adjacent, smaller clumps of dark matter. As a result of this complex evolution cluster dynamical states are also complex.The hot ICM plasma is the dominant baryonic cluster component. Because the ICM is weakly collisional it effectively captures important details of the formation dynamics and its history. While some events and processes are revealed conveniently through thermal X-ray emissions, other vital dynamical behaviors are highlighted primarily via non-thermal emissions, either within the ICM itself or through interactions between the ICM and relativistic plasmas deposited within by active galaxies. This non-thermal window into cluster formation dynamics is especially important in cluster outskirts, where thermal X-ray signals are weak. In this talk I will review these issues and some of our ongoing efforts to model and decipher distinctive non-thermal signals of ICM dynamics.