Verification and validation of renormalization group inspire particle weights for PIC codes

Summary form only given. Simulations of dense kinetic plasmas are an area of active research. A variety of devices from high power microwave devices to Hall thrusters involve situations with dense fluidlike plasmas coexisting with important kinetic non- Maxwellian particle distributions. These plasmas exhibit a range of length and time scales, making accurate simulation a challenging and computationally intensive task. Currently, we are applying renormalization group methods to provide a systematic means to investigate multi-scale plasma behavior from the kinetic to the MHD regime. One development has been the discovery of a relationship between traditional particle-in-cell weights and the renormalized charge associated with Debye shielding. The development of algorithms to handle these multi-scale circumstances is facilitated by high-fidelity test problems suitable for verification and validation studies. Specifically, we report on the development of ordinary differential equations appropriate for studying kinetic plasmas with short Debye lengths relative to the system size. Via analytic and numerical solutions, we study the impact of collective shielding on Langmuir waves. Both our analytic and PIC simulations indicate the existence of harmonic mixing driven by nonlinear excitation of Langmuir waves in highly shielded (dense) plasmas.