The Effect of Plasma Boundaries on the Dynamic Evolution of Relativistic
Radiation Belt Electrons
Abstract
Understanding the dynamic evolution of relativistic electrons in the
Earth’s radiation belts during both storm and non-storm times is a
challenging task. The U.S. National Science Foundation’s Geospace
Environment Modeling (GEM) focus group “Quantitative Assessment of
Radiation Belt Modeling” (QARBM) has selected two storm time and two
non-storm time events that occurred during the second year of the Van
Allen Probes mission for in-depth study. Here, we perform simulations
for these GEM challenge events using the 3-Dimensional Versatile
Electron Radiation Belt (VERB-3D) code. We set up the outer $L^*$
boundary using data from Geostationary Operational Environmental
Satellites (GOES) and validate the simulation results against satellite
observations from both the GOES and Van Allen Probe missions for 0.9 MeV
electrons. Our results show that the position of the plasmapause plays a
significant role in the dynamic evolution of relativistic electrons. The
magnetopause shadowing effect is included by using last closed drift
shell (LCDS), and it is shown to significantly contribute to the
dropouts of relativistic electrons at high $L^*$.