Gradual diffusion and punctuated phase space density enhancements of highly relativistic electrons: Van Allen Probes observations

Authors

D. N. Baker, University of Colorado BoulderFollow
A. Jaynes, University of Colorado Boulder
X. Li, University of Colorado Boulder
M. G. Henderson, Los Alamos National LaboratoryFollow
S. G. Kanekal, Goddard Space Flight CenterFollow
Geoffrey Reeves, Los Alamos National LaboratoryFollow
Harlan E. Spence, University of New HampshireFollow
S. Claudepierre, Aerospace CorporationFollow
Joseph F. Fennell, Aerospace CorporationFollow
M. K. Hudson, Dartmouth CollegeFollow
R. M. Thorne, University of California - Los AngelesFollow
J. C. Foster, Massachusetts Institute of Technology
P. J. Erickson, Massachusetts Institute of Technology
D. M. Malaspina, University of California - Los Angeles
J. R. Wygant, University of Minnesota - Twin Cities
A. J. Boyd, University of New Hampshire - Main CampusFollow
C A. Kletzing, University of IowaFollow
A. Drozdov, University of California - Los Angeles
Y. Y. Shprits, University of California - Los Angeles

Abstract

Abstract

The dual-spacecraft Van Allen Probes mission has provided a new window into mega electron volt (MeV) particle dynamics in the Earth's radiation belts. Observations (up to E ~10 MeV) show clearly the behavior of the outer electron radiation belt at different timescales: months-long periods of gradual inward radial diffusive transport and weak loss being punctuated by dramatic flux changes driven by strong solar wind transient events. We present analysis of multi-MeV electron flux and phase space density (PSD) changes during March 2013 in the context of the first year of Van Allen Probes operation. This March period demonstrates the classic signatures both of inward radial diffusive energization and abrupt localized acceleration deep within the outer Van Allen zone (L ~4.0 ± 0.5). This reveals graphically that both "competing" mechanisms of multi-MeV electron energization are at play in the radiation belts, often acting almost concurrently or at least in rapid succession. Key Points Clear observations to higher energy than ever before Precise detection of where and how acceleration takes place Provides "new eyes" on megaelectron Volt.

Department

Physics

Publication Date

3-2014

Journal Title

Geophysical Research Letters

Publisher

American Geophysical Union Publications

Digital Object Identifier (DOI)

10.1002/2013GL058942

Document Type

Article

Recommended Citation

Baker , D. N., et al. (2014) , Gradual diffusion and punctuated phase space density enhancements of highly relativistic electrons: Van Allen Probes observations, Geophys. Res. Lett., 41, 1351–1358, doi:10.1002/2013GL058942

Rights

©2014. The Authors.