Understanding Van Allen Radiation Belt loss processes and their impact on the upper atmosphere

As an astrophysical object, the Earth's magnetosphere appears a rather quiescent body dominated by slow dynamical processes and small magnetic fields. However, within our environment are the Van Allen Radiation Belts - torus-shaped regions of relativistic plasma whose origins and behaviour are subjects of fierce scientific debate.

Modern society is increasingly reliant on the space-based infrastructure that inhabit this region for critical services such as Earth observation, defence, telecommunications, GPS navigation, and electronic banking and energetic particle precipitation affects upper atmospheric chemistry in ways that we are only now beginning to explore.

The Radiation Belts are governed by a complex interplay between acceleration, transport and loss processes. We are starting to understand acceleration and transport, but understanding relativistic electron loss is the big unknown in Radiation Belt physics. Electrons can be lost directly through the outer boundary of the magnetosphere, or via particle precipitation into the ionosphere contributing to chemistry changes and upper atmospheric dynamical changes.

This project will make the first quantifications of loss processes during heightened geomagnetic activity, such as CMEs. We will study energetic particle data from international satellite missions such as the NASA Van Allen Probes, and a worldwide ground-based ionospheric network to validate the bedrock of our theoretical understanding of the Radiation Belts.