Kinetic Theory and Simulation of Ultra-Low-Frequency Waves in Magnetospheric Plasmas

University Of California-Irvine, Irvine CA

Investigators

Abstract

Satellites regularly observe Ultra-Low Frequency (ULF) waves in the magnetosphere. The observations strongly suggest that the observed waves correspond to nonlinear states of the magnetospheric plasma. This project will concentrate on the theoretical analysis of these waves. An existing linear gyrokinetic-magnetohydrodynamic code will be extended to the nonlinear states. The nonlinear code will then be used to study the excitation and evolution of Alfven waves in a realistic dipole magnetic field. The code will include finite magnetic compression in order to investigate magnetic compressional modes in high-beta plasmas. The linear code will also be further developed to allow it to be used to study kinetic electrostatic instabilities. The code will be used to study the stability properties of ion-temperature-gradient and trapped particle modes in dipole plasmas. Finally, extensive test-particle simulations will be used to study the process of stochastic heating of the particles via wave-particle interactions. The project involves a postdoctoral researcher, a graduate student and an Honor Senior physics major. The results will have direct bearing on satellite observations.