9312263 Grabbe Numerical development and analysis of instabilities and transport in active regions of the Earth's magnetotail will be carried out. A set of parallel processing codes will model the transport driven by instabilities associated with ion beams and currents, as well as strong drifts caused by steep gradients and strong electrostatic fields around the plasma sheet - lobe transition, under a range of magnetotail conditions. A linear code and a transport code will include kinetic parts to evaluate growth and transport driven by ion beam instabilities and electron currents, and a fluid part for growth and transport driven by gradients and electrostatic fields present near the plasma sheet boundary layer. The plasma dispersion function used for the kinetic part of the code will be generalized to a modified plasma dispersion function in which the model distribution functions for beams, currents, and background plasma can be tailored for realistic input conditions. When the codes are developed they will be used for predicting transport processes under a variety of plasma conditions for models of regions near the plasma sheet boundary layer in the Earth's magnetotail. ***
