MHD/particle simulations of radiation belt dynamics

Author
Keywords
Abstract
Particle fluxes in the outer radiation belts can show substantial variation in time, over scales ranging from a few minutes, such as during the sudden commencement phase of geomagnetic storms, to the years-long variations associated with the progression of the solar cycle. As the energetic particles comprising these belts can pose a hazard to human activity in space, considerable effort has gone into understanding both the source of these particles and the physics governing their dynamical behavior. Computationally tracking individual test particles in a model magnetosphere represents a very direct, physically-based approach to modeling storm-time radiation belt dynamics. Using global magnetohydrodynamic models of the Earth\textendashSun system coupled with test particle simulations of the radiation belts, we show through two examples that such simulations are capable of capturing the outer zone radiation belt configuration at a variety of time scales and through all phases of a geomagnetic storm. Such simulations provide a physically-based method of investigating the dynamics of the outer radiation zone, and hold promise as a viable method of providing global nowcasts of the radiation environment during geomagnetically active periods.
Year of Publication
2002
Journal
Journal of Atmospheric and Solar-Terrestrial Physics
Volume
64
Number of Pages
607-615
Date Published
04/2002
ISSN Number
13646826
URL
http://www.sciencedirect.com/science/article/pii/S1364682602000184
DOI
10.1016/S1364-6826(02)00018-4