The Earth's radiation belts consist of a population of energetic electrons that is trapped by the Earth's nominally dipole magnetic field. A major challenge in radiation belt physics is identifying and describing the various processes that contribute to the energization of the electrons, and their loss, particularly uner highly dynamic geomagnetic conditions. The aim of this 3-year project is to quantitatively understand a newly discovered wave-scattering mechanism, termed transit-time diffusion, which has the potential to play an important role in radiation belt energization. This involves scattering by fast magnetosonic waves, which is a class of waves that has not previously been considered important for this problem. A combination of modeling and analytical approaches will be used to answer a number of fundamental questions about this new mechanism and its relative importance for radiation belt dynamics compared to other wave processes.
The project will be led and carried out mainly by a team of three early-career scientist and a graduate student will also be trained as part of the project. Energetic electron fluxes in the radiation belts constitute an important space weather concern, as they are known to adversely affect space-based assets upon which modern society is increasingly dependent. Consequently, better understanding and prediction of radiation belt dynamics would be of benefit to society at large.
