Advanced numerical simulations of temperature anisotropy instabilities and collective interaction processes in high-intensity bunched ion beams

The δf particle-in-cell simulation method has been extended to allow the perturbation to be defined relative to any reference state, and a switching algorithm that can smoothly switch between the δf and total-f methods has been developed. The improved δf method has been successfully applied to simulate the collective dynamics of high-intensity bunched beams. Systematic studies of the influence of finite bunch length on the spectra of collective excitations in high-intensity ion beams, and the linear and nonlinear evolution of the temperature anisotropy instability has been carried out.