Comparison of electrical properties of ceramic insulators under gamma ray and ion irradiation

The electrical properties of ceramic insulators of Y2O3, CaZrO3 and Er2O3 were examined under gamma ray and low energy ion beam irradiation. The gamma ray induced currents increased with the bias voltage. Their radiation-induced conductivity (RIC) evaluated from the induced current was almost within one order of magnitude of that predicted from the previous fusion neutron and fission reactor irradiations. Under low energy ion beam irradiation, the induced current from the positive bias voltage was strongly suppressed. From the point of the energy deposition, the magnitude of the ion-induced current was significantly lower than that under gamma ray and neutron irradiations. A transient change in the induced current at the start of beam irradiation implies that the electric field in the specimen was affected by the unevenness of the distribution of the released electrons and holes.