Analysis of charging kinetics on space dielectrics under representative worst case geostationary conditions

Prediction of charging behaviour of space used materials often raise the issue on the definition of the applied electron energy spectrum used for irradiation under representative conditions. Radiation induced conductivity (RIC) can not be discarded for a proper qualification of these materials. But RIC level is significantly dependent upon radiation dose and dose rate. We have been able to demonstrate that the applied energy spectra lead to strong and hazardous charging levels, when radiation history is not regarded. However, charging effect is strongly smoothed by radiation history of the material. We have been able therefore to reveal in this study that a good electric qualification of space materials under electron irradiation requires the definition of realistic electron energy spectrum and implies to take into account radiation history in space.