抄録
The Active Plasma Experiment (APEX) uses intensive electron beam emission for the study of dynamic processes in the magnetosphere and upper ionosphere. The beam energy and current is as high as 8 keV and 100 mA and the pitch angle of the emission varies in the range from 50° to 80°. The basic cycle of electron injection is formed by current pulses of different duration, intensity and frequency. The spacecraft potential is balanced by a low energy xenon plasma generator during the electron beam injection. The response of the environment is studied by the PEAS charged particle spectrometer working in the energy range 0.1-25 keV. The common response to the beam emission is the increase of the intensity of the registered electrons with energy less than 2 keV. Under some circumstances (the satellite position, the injector regime, the beam direction with respect to the magnetic field etc.), strong electron fluxes of the order of 107 cm-2sec-1keV-1 have been observed. The energy of these fluxes is in general a rising function of the mean current of the emitted beam but never exceeds the beam energy. The energy-angular distribution exhibits a complicated structure with the maximum energy located at the pitch angle which corresponds to that of the emitted electron beam.
