Numerical simulation of collision-free plasma using Vlasov hybrid simulation

Summary form only given. A novel scheme for the numerical simulation of wave-particle interactions in space plasmas has been developed. The method, termed Vlasov hybrid simulation (VHS), is applicable to hot collision-free plasmas in which the unperturbed distribution function is smooth and free of delta function singularities. The particle population is described as a continuous Vlasov fluid in phase space-granularity, with collisional effects being ignored. In traditional PIC/CIC codes the charge/current due to each simulation particle is assigned to a fixed spatial grid. In the VHS method the simulation particles sample the Vlasov fluid and provide information about the value of the distribution function F(r,x) at random points in phase space. The VHS technique is also more efficient than previous Vlasov codes which performed a discretization of the Vlasov equation. The VHS technique has been applied to the problem of nonlinear wave-particle interactions in the VLF band and used to simulate rising frequency emissions triggered by Siple pulses. The code produces stable reproducible emissions whose characteristics agree with experimental observations