Abstract
Sustained periods of southward interplanetary magnetic field can result
in strong magnetospheric convection, during which, the Alfven layer,
separating regions of sunward convection and closed drift paths,
migrates earthwards. Plasmasheet electrons then have direct access to
the inner magnetosphere, traversing the dawn sector before crossing the
magnetopause, and present a potential seed population for the radiation
belts. Here we examine, for the first time, whether energetic electrons
can be sufficiently energised during their drift, via resonant
interactions with whistler-mode chorus waves, so as to pass the Alfven
layer prior to leaving the system. We utilise a natural coordinate
system for magnetosphere convection, (U,B,K) space, in which we
calculate the drift trajectories, electron energies on open drift paths,
and drift times. The acceleration time from resonant chorus-wave
particle interactions is calculated using the Versatile Electron
Radiation Belt model (VERB) first as a 2-D diffusion equation and then
in 4-D convection-diffusion mode. Comparing the drift times to the
acceleration timescales we find that interactions with chorus waves do
result in a portion of the electrons on open drift paths passing the
Alfven energy. However, whether this acceleration occurs sufficiently
quickly depends on the energy distribution of the electron population.