GEM: The Role of Wave-Particle Interactions in the Inner Magnetosphere

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

The principal objective of this project is a detailed understanding of the origin of magnetospheric plasma waves and the influences these waves have on the dynamical behavior of trapped magnetospheric particles. The path integrated growth rate and damping mechanisms for plasma waves will be studied in realistic model environments using a hot ray tracing code. This will establish the conditions for significant wave gain and the effectiveness of energy transfer, via the waves, to other components of the plasma. New codes will be developed to evaluate the rates of pitch-angle scattering and energy diffusion of resonant radiation belt particles with each important class of wave. Quantitative calculations will be made of the rate of particle precipitation loss to the atmosphere and of the time-scale for stochastic acceleration under different levels of geomagnetic activity. The time-scales for loss and local acceleration will be incorporated into a radial diffusion code, to model the structure of the electron radiation belts and their variability during geomagnetic activity. The excitation of plasma waves and their effect on energetic ion and electron losses will be examined as will the mechanisms responsible for acceleration of energetic electrons to relativistic energies during magnetic storms. The project will lead to a global understanding of dynamics of the ring current during magnetic storms. A synoptic model of the wave-particle processes will be developed for future integration into a Geospace General Circulation Model.