An Early-Stage Plasmasphere Refilling Model Based on a Kinetic Approach with Trapping Due to Ion Heating and Pitch-Angle Scattering
- Gordon R. Wilson
Published Online: 18 MAR 2013
Copyright 1991 by the American Geophysical Union.
Modeling Magnetospheric Plasma Processes
How to Cite
Lin, J., Horwitz, J. L., Wilson, G. R. and Ho, C. W. (2013) An Early-Stage Plasmasphere Refilling Model Based on a Kinetic Approach with Trapping Due to Ion Heating and Pitch-Angle Scattering, in Modeling Magnetospheric Plasma Processes (ed G. R. Wilson), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM062p0151
- Published Online: 18 MAR 2013
- Published Print: 1 JAN 1991
Print ISBN: 9780875900285
Online ISBN: 9781118663905
- Space plasmas—Mathematical models—Congresses;
- Magnetosphere—Mathematical models—Congresses
We hypothesize that, in the early stage of replenishment of plasmaspheric flux tubes following magnetic storms, two important processes in the trapping and accumulation of plasma occur through stochastic wave-driven pitch-angle scattering and perpendicular heating of inflowing ionospheric particles. By treating the motion of particles as basically adiabatic but incorporating velocity-space diffusion associated with (1) pitch-angle scattering arising from ion interactions with left-hand circularly polarized electromagnetic waves and (2) perpendicular ion heating due to electromagnetic ion cyclotron waves, we calculate (a) bouncing ion trajectories, and (b) large-scale density evolution of ‘polar wind' ionospheric ions flowing onto a closed L=4 flux tube. It is found that relatively modest power levels of wave-particle interactions lead to important effects on ion trajectories including decreasing mirror latitudes and sometimes significant and abrupt equatorial entrainment of these ions. Also, significant general accumulation of plasma all along the magnetic flux tube with up to 10 or more ions/cc in the equatorial regions after about 12 hours following initiation of refilling is observed.