PECULIARITIES OF A RADIATION DEFECT CREATION IN BERYLLIUM-OXIDE CRYSTALS

The radiation defect formation has been studied in beryllium oxide cry stals irradiated with reactor neutrons in a wide range of fluences (10 (15)-10(20) cm(-2)). It has been found that at high dose irradiation t he saturation and reduction of anion and cation vacancies (the simples t point radiation defects) occurs in contrast to another alkaline eart h oxides where only saturation takes place. A reduction of the point r adiation defects under high dose irradiation has been caused not only by achieving a dynamic balance between creation and annihilation of Fr enkel pairs but also by aggregation of the defects created. The mechan ism of defect aggregation is discussed for the simplest aggregate defe ct-P--center (double cation-anion vacancy trapping an electron). A new aggregate paramagnetic centers have been registered in high-dose neut ron irradiated BeO crystals.