Hybrid Particle-In-Cell Simulation of Wave-Particle Interactions in Collisionless Plasma with FD and DG Schemes

The plasma environment of the Earth's magnetosphere is frequently unstable to very low frequency (VLF: 3–30 kHz) waves, leading to a wide variety of natural emissions and wave amplification phenomena
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. Modeling VLF wave phenomena in this environment remains a significant computational challenge because the characteristic frequencies of a plasma may be an order of magnitude higher than the VLF frequencies of interest. This discrepancy presents a significant problem for time-domain numerical solution methods such as finite difference time-domain (FDTD) because explicit time-stepping techniques are limited by the largest characteristic frequency present in the system. Another time-domain solution technique, called the discontinuous Galerkin (DG) method, does not suffer from these restrictions. Due to its different formulation, the DG method is easily adapted for use on unstructured grids, allowing for increased spatial resolution only where it is required.