[PEM21-P07] Numerical Modeling of Plasma Wave Electric Field Effects on Spacecraft Charging
Keywords:plasma wave, spacecraft charging, wave electric field, chorus waves, photoelectron emission, particle-in-cell simulation
In this paper, we perform plasma particle simulations to address such unresolved issues. Our original PIC simulation code EMSES has a capability of reproducing plasma wave excitation/propagation as well as spacecraft charging in a self-consistent manner. Meanwhile, such analysis with realistic physical parameters requires too large computational resources, because the typical spatial scale of plasma wave lengths is much greater than that of the near-spacecraft environment. Thus, we propose another modeling of the phenomena by applying a spatially-uniform and time-varying electric field to the whole simulation domain as an external force term. We have confirmed that this model can reproduce the photoelectron-driven spacecraft potential fluctuations in case of a circular-polarized wave electric field. We have also constructed a theoretical model to explain the simulated potential fluctuations in consideration of a photoelectron escaping current though an RF sheath around the spacecraft [Boehm et al., 1994].