Three-dimensional particle simulation of heavy-ion fusion beams

The beams in a heavy‐ion‐beam‐driven inertial fusion (HIF) accelerator are collisionless, nonneutral plasmas, confined by applied magnetic and electric fields. These space‐charge‐dominated beams must be focused onto small (few mm) spots at the fusion target, and so preservation of a small emittance is crucial. The nonlinear beam self‐fields can lead to emittance growth, and so a self‐consistent field description is needed. To this end, a multidimensional particle simulation code, warp [Friedman et al., Part. Accel. 37‐38, 131 (1992)], has been developed and is being used to study the transport of HIF beams. The code’s three‐dimensional (3‐D) package combines features of an accelerator code and a particle‐in‐cell plasma simulation. Novel techniques allow it to follow beams through many accelerator elements over long distances and around bends. This paper first outlines the algorithms employed in warp. A number of applications and corresponding results are then presented. These applications include studies ...