Northern Illinois University, DeKalb, Illinois, USA
Dynamic Coulomb expansion of dense particle bunches can lead to transverse density shock-like propagation for nonuniform bunch distributions. Furthermore, under favorable circumstances, multiple bunches in close proximity can collide without crossing to form wheel-and-spoke patterns. This process has been observed experimentally for Rubidium ions, but not yet for electrons, where the dynamics occur over far shorter length scales. We simulate the interaction of electron bunches while varying the initial transverse temperature and density profiles to determine the thresholds that characterize this pattern formation. Additionally, we consider the effects of asymmetries and the impact of a low-density halo on the overall process. The simulations are conducted using a novel high-fidelity algorithm for collisional particle dynamics.
