Solar energetic particle (SEP) events result from solar flares or from shock waves associated with Coronal Mass Ejections. The particles consist of both ions and electrons that have relativistic energies and reach Earth within minutes to a few hours of the event that initially generated the particles. Because of their very high energies and the speed with which they reach the Earth, these events represent significant space weather hazards. Within Earth's magnetosphere there is often a large difference between the eastward and westward fluxes of the energetic particles. This project will generate a physics-based, quantitative model of the particle fluxes within the magnetosphere at locations where direct observations are unavailable.
The project will utilize global test particle simulations within an empirical magnetosphere mdoel that is driven by the solar wind parameters. The simulations will investigate the electric current systems within the magnetosphere that lead to variations in the geomagnetic cutoffs of the particles. Data from the GOES geosynchronous satellites will be used to determine the magnitude of the east-west asymmetry. It will establish statistical relationships between the state of the solar wind and the relative magnitudes of the eastward and westward particle fluxes.
