Main-phase creation of "seed" electrons in the outer radiation belt

During a geomagnetic storm in early November 1993, NOAA satellite observati ons revealed that a population of energetic electrons appeared in the cente r of the outer radiation belt during the main phase of the storm. At the be ginning of the main phase of the magnetic storm, the number of electrons wi th energies from 30 keV to 100 keV increased rapidly and contributed to bui ld up of the ring current. At the end of the main phase the flux of electro ns with energies greater than 300 keV increased significantly. Akebono sate llite observations showed that the flux of electrons with energies ranging from 300 keV to 950 keV increased late of the storm main phase and that the flux of electrons with energies from 950 keV to 2.5 MeV increased during t he storm recovery phase. The electron flux increase observed by both NOAA a nd Akebono took place first in the central part of the outer radiation belt (L similar to 4) and propagated to higher L shells with a significant time delay. We think that the ring current electrons that appeared first and ne ar L similar to 4 during the main phase seeded the subsequent increase in t he flux of MeV electrons in the entire outer radiation belt.