Ground-based VLF measurements during pulsed electron beam emissions in the ionosphere

The major objective of the CHARGE-2B sounding rocket experiment is the generation of VLF waves using a pulsed electron beam from an ionospheric platform. The sounding rocket payload included the mother section that carried the 3-keV, 2-A electron gun, a tethered daughter and a free flying diagnostics package, both with wave receivers. The experiment included four ground-based VLF wave receivers located near the ground point of the geomagnetic field line connecting the beam-emitting payload to the Earth. Initial analysis of ground-based measurements has not shown any VLF emissions correlated with electron gun operations, although VLF signals from the beam emissions were detected by both the daughter and free flyer in the ionosphere.