Observation of particle flux and damage on IC devices in the radiation belt with AKEBONO satellite

Observation has been continuing on high energy particles and their effects on IC devices by using the radiation monitor, RDM, boarding on AKEBONO, since it was launched on February 22, 1989. The energy spectra and the intensity distributions of geomagnetically trapped charged particles (proton, electron and alpha particle) were measured during the period that the satellite passed through the high intensity area of the radiation belt. From the comparison between the observed data and the results calculated with the NASA models AP8 for potons and AE8 for electrons, it was found that the spatial distribution of observed particle intensities gave pretty good agreement with the models, but our absolute values were a factor of 2 to 10 deviated from the models' value. Single event effects on IC devices caused by energetic charged particles were observed together with charged particle intensities and the strong correlation was found between these two. This confirmed that the single event upsets were caused mainly by energetic protons in the radiation belt. These observed results may be quite useful for evaluating the absorbed dose and the radiation damage on IC devices in the space environment. (author)