First IMAGE-ing of Particle Acceleration by Dynamic Magnetic Fields (HENA)
Magnetic storm particle acceleration before IMAGE:
- Tail magnetic field relaxes impulsively
- Energetic particle fluxes increase
- Auroral brightens and expands
What is happening here?
- Particles injected from tail?
- Particles released from radiation belts?
IMAGE-ing by HENA (next page) reveals:
- Pre-existing dense plasma sheet
- Moves Earthward and fluxes intensify
- Particles are accelerated and injected, intensifying fluxes closer to Earth, as magnetic field relaxes abruptly.
- Consistent with model of Fok et al., JGR 1999.