Session LO2 - Ion and Electron Beams, Coherent Radiation Generation.
ORAL session, Wednesday afternoon, October 31
Room 203AB,
The propagation of a high-current finite-length ion charge bunch through a background plasma is of interest for many applications, including heavy ion fusion, plasma lenses, cosmic rays, etc.. Charge neutralization has been studied both analytically and numerically during ion beam entry, propagation, and exit from the plasma. A suite of codes has been developed for calculating of the degree of charge and current neutralization of the ion beam pulse by the background plasma. The code suite consists of two different codes: a fully electromagnetic, relativistic particle-in-cell (PIC) code, and a relativistic Darwin model for long beams. As a result of a number of simplifications the second code is hundreds of times faster than the first one and can be used for most cases of practical interest, while the first code provides important benchmarking for the second. The analytical theory has been derived using the assumption of long charge bunches and conservation of generalized vorticity. The analytical results agree well with the results of numerical simulations for ion beam charge and current neutralization. The numerical simulations also show complex phenomena during beam entry into the plasma.