SM52A-06
Superposed Epoch Analysis Comparing the Reaction of the Proton Radiation Belt and the Electron Radiation Belt during High-Speed-Stream-Driven Storms

Friday, 18 December 2015: 11:35
2018 (Moscone West)
Joseph Borovsky1, Thomas E. Cayton2, Michael Denton3, Richard D Belian4, Rodrick A Christensen5 and John C Ingraham5, (1)Space Science Institute Los Alamos, Los Alamos, NM, United States, (2)Retired, Rio Rancho, NM, United States, (3)Space Science Institute Boulder, Boulder, CO, United States, (4)Retired, Tesuque, NM, United States, (5)Retired, Los Alamos, NM, United States
Abstract:
In the years 1976 - 1995, the CPA ion and electron energetic-particle detectors were operated on multiple geosynchronous-orbit spacecraft. Unlike later instruments at geosynchronous orbit, the CPA detectors had separate ion and electron instruments and the ion instruments did not suffer from false counts caused by energetic electrons. Hence, the ion-radiation-belt measurements by the multispacecraft CPA detectors are of high quality. Contrary to common opinion, the proton radiation belt at geosynchronous orbit is robust; its number density is about 10 times higher than the number density of the electron radiation belt. Recently, (1) reprocessed CPA proton and electron measurements have become available for the years 1976-1995 and (2) a collection of 53 high-speed-stream-driven storms in the years 1976-1992 have been identified. These 53 storms are used to examine the evolution of the proton and electron radiation belts at geosynchronous orbit in high-speed-stream storms. The pre-storm decay, the early storm dropout, the sudden recovery, and the slow long-duration stormtime hardening of the spectra are examined. Some of the stormtime phenomena are similar between protons and electrons (i.e. the pre-storm decay, dropout, and sudden recovery) and some are different (the longtime enhancement during extended storms). The question is posed: Do similar behaviors of the protons and electrons imply that the same physical processes are acting on both populations?