Relevance of Ground-based Electron-Induced Electrostatic Discharge Measurements to Space Plasma Environments

Electron-induced electrostatic discharge (ESD) can lead to severe spacecraft anomalies. It is crucial to the success of space missions that the likelihood of ESD occurrence is understood and mitigated. To aid in predicting ESD occurrence, a model for electric fields above and below the charge layer inside an electronirradiated dielectric material was developed. An instrumentation system was also designed to induce and detect ESD events. Because ESD events with a wide range of maximum current values can occur over a range of time intervals, multiple simultaneous detection methods were employed as charge was accumulated on a sample surface; these included monitoring of sample current and optical emissions from the sample surface. Data from ESD experimentation for James Webb Space Telescope (JWST) materials was used to verify that the instrumentation system was effective in inducing and observing ESD. Two types of discharge events were observed during JWST testing: a sudden-onset, decaying current accompanied by luminescence in the optical data, and an arc or flash in optical data. JWST test results were applied to the electric field models developed to determine the threshold electric field for luminescence onset. The models were also applied to the JWST materials in five different space plasma environments to determine the accumulated electric field as a function of time, and to thereby predict the likelihood of sample luminescence in each location