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Title: Energy-dependent dynamics of keV to MeV electrons in the inner zone, outer zone, and slot regions

Here, we present observations of the radiation belts from the Helium Oxygen Proton Electron and Magnetic Electron Ion Spectrometer particle detectors on the Van Allen Probes satellites that illustrate the energy dependence and L shell dependence of radiation belt enhancements and decays. We survey events in 2013 and analyze an event on 1 March in more detail. The observations show the following: (a) at all L shells, lower energy electrons are enhanced more often than higher energies; (b) events that fill the slot region are more common at lower energies; (c) enhancements of electrons in the inner zone are more common at lower energies; and (d) even when events do not fully fill the slot region, enhancements at lower energies tend to extend to lower L shells than higher energies. During enhancement events the outer zone extends to lower L shells at lower energies while being confined to higher L shells at higher energies. The inner zone shows the opposite with an outer boundary at higher L shells for lower energies. Both boundaries are nearly straight in log(energy) versus L shell space. At energies below a few 100 keV, radiation belt electron penetration through the slot region into the innermore » zone is commonplace, but the number and frequency of “slot filling” events decreases with increasing energy. The inner zone is enhanced only at energies that penetrate through the slot. Energy- and L shell-dependent losses (that are consistent with whistler hiss interactions) return the belts to more quiescent conditions.« less
 [1] ;  [1] ;  [1] ;  [2] ;  [2] ;  [3] ;  [3] ;  [3] ;  [4] ;  [5] ;  [3] ;  [6]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States); The New Mexico Consortium, Los Alamos, NM (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. The Aerospace Corporation, Los Angeles, CA (United States)
  4. The New Mexico Consortium, Los Alamos, NM (United States)
  5. Univ. of New Hampshire, Durham, NH (United States)
  6. Univ. of Colorado Boulder, Boulder, CO (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2169-9380
Grant/Contract Number:
NAS5-01072; AC52-06NA25396
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 1; Journal ID: ISSN 2169-9380
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
Country of Publication:
United States
OSTI Identifier: