| The acceleration mechanisms of electrons are presently a heavily debated topic. The sudden appearance of a new electron radiation belt can produce a dramatic and long-lasting influence on the Earth's space environment. One such event took place on March 24, 1991 at approximately 2.5 Re, as observed by CRRES (Combined Radiation and Release Experiment Satellite). This prompt electron acceleration has been determined to be the result of an interplanetary shock impacting the Earth's magnetosphere. To understand how electrons surrounding the Earth are affected when such a shock encounters the magnetosphere, a phase space density study and a parametric study of a test-particle simulation similar to the Li et al. [1993] work is performed. Shock-induced enhancements are one extreme example of an electron energizing process, but which acceleration mechanisms typically dominate remains a currently disputed issue. Pitch angle distribution averages from the CRRES data and their evolution are analyzed for clues to this debate. This work begins with a study of the event of March 24, 1991, which was a prompt, shock-induced energization. The previous work is extended and a type of analysis called a phase space density study, which can be used to determined the adiabaticity of a process, is performed. Because of the huge impacts on the Earth's space environment created by enhancements of this magnitude, it is interesting to study how difficult it is to produce them and under what magnetospheric differences they are affected. A parametric study varying the physical parameters assumed under the Li model is performed. The study is then expanded to look at the rest of the data from the CRRES satellite mission, which observed the March 24, 1991 event, in order to provide insight into to the physical mechanisms at work on magnetospheric electrons. |
