Inner Magnetospheric Electric Field and its Influence on Plasmasphere
Erosion and Plasma Sheet Access
Abstract
The large-scale electric field in the inner magnetosphere is a key
driver of many processes and the dynamics of magnetospheric plasmas.
During geomagnetic storms, the enhanced convection electric field is
responsible for eroding the plasmasphere and for moving the inner edge
of the plasma sheet earthward. In this presentation, we show the
preliminary results of an examination of the distribution and variations
of the inner magnetospheric quasi-static electric field as measured by
the Electric Field and Waves (EFW) instruments onboard the twin
spacecraft of the Van Allen Probes mission. We investigate the role that
the electric field plays in plasmasphere erosion and plasma sheet access
to the inner magnetosphere by analyzing the electric field measurements
in conjunction with cold plasma density and plasma sheet particle flux
measurements. Since the coupling between plasma populations in the
magnetosphere is inherently related to the electric field, we expect
that the combined measurements of the electric field and plasmas will
enhance our understanding of the physical processes that drive the
magnetospheric dynamics.