Some Features of the Radiation Resistance of Composite Scintillators

This paper describes studying the radiation resistance of the composite scintillators based on grains of some inorganic crystals, namely, GSO:Ce, GPS:Ce, YSO:Ce, YAG:Ce, and Al2O3:Ti. The study of composite scintillators containing the inorganic grains shows that these scintillators are resistant to radiation up to doses of more than 125 Mrad, and some of them up to doses not lower than 550 Mrad.The paper studies possible processes of radiation-induced changes arising in scintillators under the irradiation as well as analyzes the effect of these processes on the radiation resistance. The grains are the crystalline material. All crystalline scintillation materials contain defects, which can play the role of either luminescence or quenching centers. The influence of irradiation results in destruction not only the main material, but such the centers. As a result, the luminescence intensity can grow for a while. The shape of the luminescence spectra does not change under various doses of irradiation because no new luminescent centers are generated. The modification of the luminescence centers should result in a change of the luminescence spectral characteristics.So, in the composite scintillators, which are containing grains of inorganic crystals, the variation of luminescence spectral characteristics either can or cannot take place. Therefore, to identify the possible processes giving rise to radiation-induced changes in scintillators, it makes sense to carry out such spectral researches before and after the irradiation.