Laboratory Investigation of Nonlinear Whistler Wave Processes

Abstract:

Nonlinear interactions involving whistler wave turbulence can strongly effect the dynamics of the radiation belts. The building blocks of whistler wave turbulence are currently being studied in the NRL Space Physics Simulation Chamber (SPSC) under scaled magnetospheric conditions. These processes include parametric three-wave decay and a nonlinear wave-particle scattering off of thermal electrons that can substantially change the wave vector direction and energy flux. In the laboratory experiments, both of these processes have been observed and characterized. The results are consistent with theoretical predictions. Additional experiments at the NRL SPSC have investigated other nonlinear wave-particle interactions. Results from continuing laboratory experiments demonstrating triggered emissions and chorus-like emissions via nonlinear whistler wave-energetic particle interactions will be discussed. These chirped whistler waves are also observed to exhibit three-wave decay/coalescence and wave-particle scattering.