Energetic Particle Injections: It’s Causes and Effects

Energetic particle injections in the inner magnetotail are a characteristic indicator of the onset of the substorm expansion phase. They are identified by the sudden increase of the particle fluxes at energies from tens to hundreds of keV, which are termed as the source and seed population of the relativistic radiation belt population, respectively. One of the consequences of these particle injections is their resultant effect on the radiation belts. The source population injected by substorms is thought to feed the temperature anisotropy, which causes whistler mode chorus wave growth. These energised chorus waves then accelerate the seed population. This is a key mechanism considered for achieving electrons with relativistic energies in the radiation belts which can be harmful to space-based infrastructure, making this area of study important from an operational perspective. Another consequence of energetic particle injections is particle precipitation, which is the loss of electrons to the upper atmosphere that produce auroral emissions and can deplete the ozone layer. The opportunities granted to us by current satellites and ground-based instruments make now an ideal time to consolidate current knowledge about energetic particle injections and identify open questions in preparation for new upcoming missions. The coordinated analysis of past and future datasets will give us unprecedented coverage of the magnetotail, radiation belts and ionosphere, allowing us to potentially answer some of the pressing questions brought up in this specialist discussion meeting.

The focus of this meeting will be on the causes and effects of particle injections, covering their transport from the middle magnetotail to geosynchronous orbit, the dynamics of the injection boundary, their effects on particle acceleration and loss, and their impacts on the atmosphere and infrastructure. Papers on both observations and modelling of this topic will be invited, highlighting results related to the phenomenon and how upcoming missions may be utilised effectively.

We propose a schedule as follows:

10:00 Arrival

10:30 Introduction

Morning Session

10:40 First invited speaker

The morning session then continues until 13:00

13:00 – 14:00 Lunch

Afternoon Session

14:00 Second invited speaker

The afternoon session then continues until 15:20

15:20 Concluding Summary

15:30 End meeting

Organisers:

Christian Lao (UCL)

Dovile Rasinskaite (Northumbria)