Analysis of Charging Kinetics on Space Dielectrics Under Representative Worst Case Geostationary Conditions

Prediction of the surface charging behavior of the materials used in space often raises concerns about the definition of the applied electron energy spectrum used for irradiation during testing. Radiation-induced conductivity (RIC) cannot be discarded for a proper qualification of these materials. But RIC level is significantly dependent upon radiation dose and dose rate. We have demonstrated that for some energy spectra, severe potentially hazardous charging levels were predicted by models when radiation history was ignored. However, the charging effect is strongly smoothed by the radiation history of the material. We have been able therefore to reveal in this paper 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.