Collaborative Research: Quantifying the Effects of Nonlinear Wave-particle Interaction in the Inner Magnetosphere

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

Whistler waves are radio waves produced at very low frequencies by lightning. They are believed to have an important role in the dynamics of the radiation belts and broader magnetosphere. This work will involve theoretical and observational studies of these waves and their interactions with relativistic particles in the magnetosphere. The results have direct applications in space weather models, which are a priority set out in the National Space Weather Action Plan. Additionally, two graduate students will be supported and collaborations will be strengthened between plasma physicists and space physicists at multiple institutions. To quantify nonlinear wave-particle resonant interactions, three questions will be addressed (i.e., objectives) in this project: (1) how often sufficiently intense whistler waves are detected in the inner magnetosphere, which will provide the occurrence rate of nonlinear wave-particle interactions; (2) how to describe the impact of intense whistler waves on electron flux evolution, which will provide a theoretical tool to evaluate electron distributions in the geospacer system with nonlinear wave-particle interactions; and (3) what is the effect of nonlinear wave-particle interactions on wave generation and damping, which will provide a validated model of the nonlinear wave growth/damping rate in the inner magnetosphere. Each of the three objectives combines observational (from THEMIS and Van Allen Probes) and theoretical investigations. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.