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Title: Effects of ULF waves on local and global energetic particles: Particle energy and species dependences

After 06:13 UT on 24 August 2005, an interplanetary shock triggers large-amplitude ultralow-frequency (ULF) waves (|δB| ≥ 15 nT) in the Pc4–Pc5 wave band (1.6–9 mHz) near the noon geosynchronous orbit (6.6 RE). The local and global effects of ULF waves on energetic particles are observed by five Los Alamos National Laboratory satellites at different magnetic local times. The large-amplitude ULF waves cause the synchronous oscillations of energetic electrons and protons (≥75 keV) at the noon geosynchronous orbit. When the energetic particles have a negative phase space density radial gradient, they undergo rapid outward radial diffusion and loss in the wave activity region. In the particle drift paths without strong ULF waves, only the rapidly drifting energetic electrons (≥225 keV) display energy-dispersive oscillations and flux decays, whereas the slowly drifting electrons (<225 keV) and protons (75–400 keV) have no ULF oscillation and loss feature. When the dayside magnetopause is compressed to the geosynchronous orbit, most of energetic electrons and protons are rapidly lost because of open drift trajectories. Furthermore, the global and multicomposition particle measurements demonstrate that the effect of ULF waves on nonlocal particle flux depends on the particle energy and species, whereas magnetopause shadowing effect is independent ofmore » the energetic particle species. For the rapidly drifting outer radiation belt particles (≥225 keV), nonlocal particle loss/acceleration processes could also change their fluxes in the entire drift trajectory in the absence of “ Dst effect” and substorm injection.« less
Authors:
ORCiD logo [1] ; ORCiD logo [1] ; ORCiD logo [1] ;  [2] ;  [1] ; ORCiD logo [3] ;  [4]
  1. Beihang Univ., Beijing (China)
  2. Nanjing Univ. of Aeronautics and Astronautics, Nanjing (China)
  3. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  4. Univ. of Colorado, Boulder, CO (United States)
Publication Date:
Report Number(s):
LA-UR-17-28044
Journal ID: ISSN 2169-9380; TRN: US1703022
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 11; Journal ID: ISSN 2169-9380
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
National Aeronautic and Space Administration (NASA); USDOE
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics; fluctuation of solar wind dynamic pressure; large-amplitude ULF waves; oscillation and loss of outer radiation belt energetic particles; negative radial gradient of energetic particle phase space density; outward radial diffusion; magnetopause shadowing
OSTI Identifier:
1402659