Low Frequency Plasmaspheric Hiss Wave Activity Parameterized by
Plasmapause Location: Models and Simulations
Abstract
Plasmaspheric hiss waves are a dominant source of scattering for keV –
MeV radiation belt electrons within the plasmasphere. Previous
simulation and modeling work concerning hiss waves has often
incorporated them via particle-based parameterizations (e.g., L-shell).
However, recent work has shown that not only is hiss wave power loosely
dependent on L-shell, but that proximity to the plasmapause may yield
more accurate wave power distributions as it pertains to the modeling
and scattering of electrons. This work serves to expand upon those
previous studies by creating a low frequency (20 – 150 Hz) hiss wave
model and incorporating a previously crafted high frequency
(> 150 Hz) hiss wave model based on plasmapause location,
proximity to the plasmapause, and Kp activity level. Diffusion
coefficients created using this method produced shorter lifetimes for
electrons between ~300 keV – 4 MeV than their L-sorted
counterparts. Furthermore, 3D-simulations using and comparing the
different hiss wave models (plasmapause sorting vs. L-sorting) find that
the plasmapause based approach yields more accurate results when
compared to Van Allen Probe-A observations.