Van Allen Probes Observations of the Magnetospheric Response to Transient Solar Wind Features

Abstract:

We present NASA Van Allen Probes observations of the magnetospheric response to
interplanetary shocks and other solar wind discontinuities. In particular, we focus on the
energetic particle response, as observed by the Energetic Composition and Thermal Plasma
(ECT) Suite. Several Van Allen Probes studies have described drift-resonant interactions between
both energetic electron and protons (~100 keV) and poloidal mode ultra-low frequency waves in
the mHz range. In these events, charged particle energy is resonantly exchanged between the
particles and electromagnetic waves, with the ultimate energy source lying in the solar wind. We
expand upon these studies and also examine electron and proton drift-echoes, which are
regularly observed by Van Allen Probes following shocks and other solar wind discontinuities.
Finally, we present results from global MHD simulations of the solar
wind/magnetosphere/ionosphere interaction, which help place the local, in-situ observations in a
global context.