PARTICLE-IN-CELL PLASMA SIMULATIONS OF THE MODIFIED 2-STREAM INSTABILITY

We model the modified two-stream plasma instability occuring in the io nospheric E-region using a 2.5-dimensional particle-in-cell code. Comp ared to previous similar work we concentrate on simulated quantities t hat can easily be measured in the real ionosphere by coherent radars o r rockets, such as the Doppler velocity, the backscattered power, back scattered spectra, aspect angle behaviour and electron temperature enh ancement. Despite using a relatively small simulation model, we obtain remarkably good agreement between actual observed and simulated plasm a parameters. The advantage of such a small system is that we were abl e to perform (other than in previous related work) many simulation run s with different sets of input parameters, thus studying the unstable plasma under various conditions.