Modeling inner magnetospheric electric fields: latest self-consistent results

S. Sazykin, R.W. Spiro, R.A. Wolf, F.R. Toffoletto, 


This paper presents some of the latest results of self-consistent numerical
modeling of large-scale inner-magnetospheric electric fields obtained with the
Rice Convection Model (RCM).  The RCM treats plasma drifts, electric fields, and
currents in the inner magnetosphere self-consistently in the quasi-static
(slow-flow) approximation under the assumption of isotropic pitch-angle
distribution. Event simulations of the magnetic storm of March 31, 2001 are used
with two newly available RCM input models: an empirical model of the storm-time
magnetospheric magnetic field, and an empirical model of the plasma sheet. 
Results show that the effect of severe distortion of the magnetic field during
very large magnetic storms improves the ability of the RCM to predict the
location of Sub-Auroral Polarization Stream (SAPS) events, although there is not
perfect agreement with observations.  Weakening of shielding by region-2
Birkeland currents during times of severe magnetic field inflation also improves
comparison of the RCM-computed plasmapause location with data.  Results of
simulations with plasma boundary sources varying in response to measured solar
wind inputs show that the plasma sheet may become interchange unstable under
certain geomagnetic conditions.

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The Inner Magnetosphere: Physics and Modeling, 
AGU Geophysical Monograph 155, 263-270, 2005.