Remote spacecraft observations of waves excited by the pulse electron beam injected into ionosphere

Abstract In the Apex project the modulated electron beam (pulses of 2 micro sec duration, E=8 keV, I=0.1 A and 25 micro sec repetition) was emitted from a main satellite. The RF emissions were observed in parallel on the mother satellite as well as on Magion-3 subsatellite. The paper discusses the case when the subsatellite was separated about 200 km from the main object and the electron gun was operated. Together with strong electrostatic emission at the upper hybrid plasma frequency on the main spacecraft, selected spikes in RF frequency range on Magion-3, were simultaneously detected, which can be related to pulse electron beam emission.