On-orbit insulator charge storage and partial discharge in thespace radiation belts

摘要

The internal discharge monitor (IDM) has been flying on the CRRESspacecraft and sampling insulator discharge pulses from 16 samples for14 months. The instrument has worked nearly flawlessly and has recordeda total of approximately 4300 electric pulses from the 16 samples. Thetime of occurrence of each pulse is known within 32 seconds and can becompared to the space radiation spectra which are being simultaneouslyrecorded by several radiation spectrometers on the same satellite. Anexperiment was performed to determine how often radiation-inducedpulsing occurs on unbiased insulators in space. It was found that darkconductivity in the insulators is so small that there is no clearevidence of a strong roll-off in the pulsing rate at the low radiationfluxes in space. The results may also be interpreted to mean that darkconductivity has decayed in space, resulting in the pulse rate per unitelectron flux increasing over time