# On the statistics of acceleration and loss of relativistic electrons in the outer radiation belt: a superposed epoch analysis

## TL;DR

This study analyzes how solar wind and magnetospheric disturbances influence relativistic electron dynamics in the outer radiation belt, highlighting the roles of wave activity and seed populations in electron enhancements and depletions.

## Contribution

It provides a comparative analysis of electron enhancement and depletion events using phase space density and wave activity data during the Van Allen Probes era, revealing mechanisms behind electron dynamics.

## Key findings

- Magnetopause shadowing and Pc5 wave-driven diffusion are common in both events.
- Enhanced seed populations and chorus activity contribute to electron replenishment.
- Inward diffusion accelerates relativistic electrons during enhancements.

## Abstract

We investigate the response of the outer Van Allen belt electrons to various types of solar wind and magnetospheric disturbances. We use electron phase space density (PSD) calculations as well as concurrent Pc5 and chorus wave activity observations in the outer belt during the Van Allen Probes era to compare 20 electron enhancement and 8 depletion events. Results indicate that the combined effect of magnetopause shadowing and outward diffusion driven by Pc5 waves is present in both groups of events. Furthermore, in the case of enhancement events, the synergy of enhanced seed population levels and chorus activity -- due to the enhanced substorm activity -- can effectively replenish the losses of relativistic electrons, while inward diffusion can further accelerate them.