3D Simulation of the Quasilinear Electron-Langmuir Wave Interaction in Type III Solar Radio Bursts

Abstract

This thesis presents a three-dimensional relativistically correct model of the electron beam-Langmuir wave interaction in the solar corona, as well as a model of the radial electron density profile of the ambient solar plasma through which an electron beam passes. 1D models of the beam/plasma interaction have long been used, as have empirical fits for the electron density profile. In support of the overall goal of this thesis, to develop a more realistic understanding of the plasma physics processes underlying Type III solar radio bursts, we first present strong evidence for a new and physically significant analytic model for the radial density profile in the corona. The thesis then demonstrates the need to develop a 3D picture of the resonance between streaming electrons and Langmuir waves, and the coupled evolution of this system. A new picture of quasilinear relaxation of electron beams is described qualitatively and quantitatively. This 3D picture changes the way electron distributions are considered in terms of their stability or instability to the growth of Langmuir waves. The thesis also develops a numerical method utilising the analytical development of the 3D model, with initial tests and examples described in detail.