THEORY OF DIFFUSION-CONTROLLED DEFECT AGGREGATION UNDER IRRADIATION -A COMPARATIVE-STUDY OF 3 BASIC APPROACHES

Recent advances achieved within the framework of three basic theoretic al approaches to the diffusion-controlled clustering of similar defect s during irradiation are compared. These approaches (which can be iden tified as respectively macroscopic, mesoscopic and microscopic formali sms) have in common that they predict the existence of a critical dose rate for aggregation which increases with temperature, and a bell-sha ped temperature dependency of the aggregation rate. Mesoscopic and mic roscopic approaches demonstrate that the elastic interaction between r adiation defects plays a decisive role in the aggregation process. Res ults which are obtained via the different approaches are illustrated f or NaCl crystals.