A finite-circuit-element code for modeling the compression of a gyrating charged-particle beam

A method is described for calculating the interaction between an imploding liner, a magnetically confined charged-particle ring (Astron e-layer, ion ring) and a target plasma, based on the equations of the equivalent circuit. Expressing the electrodynamical behavior in terms of inductive coupling between circular current loops, so that changes in geometry and plasma parameters are described by changes in the induction coefficients, means that only ordinary differential equations arise, in contrast with fluid descriptions. Induced electron currents are conveniently included in the model. Application to a beam-target fusion system driven by the compression of an ion ring is described as an illustration of the utility of the technique.