An Eulerian Vlasov-Hilbert Code for the Numerical Simulation of the Interaction of High-Frequency Electromagnetic Waves with Plasma

Abstract

In order to handle one-dimensional spatial problems in plasmas with very high frequency electromagnetic waves (ω ⪢ ωp), the 1 - 1/2D Eulerian Vlasov code has been modified to interface with the ponderomotive force associated with the complex envelopes of the high frequency electromagnetic fields rather than the fields themselves. The ponderomotive force for the Vlasov code has been computed from the complex amplitude equations and the real Vlasov density perturbations have been converted to complex amplitude form for the mode equations via the Hilbert transform. The resulting Vlasov-Hilbert code allows us to handle high-frequency problems with complex amplitude equations for high frequency electromagnetic waves with the Vlasov code only for the relatively low-frequency plasma wave. Computations are made with this model to situations typical of forward Raman scattering and beatwave; results are in accordance with other computational methods such as full electromagnetic Vlasov-Maxwell code or envelope equations whenever they can be used. This model provides a saving of order (ωpump/ωplasma)2 (i.e., time × space) in computer time, as compared with the direct full electromagnetic Vlasov-Maxwell method with the highest space-time resolution required.