Photoluminescence dose dependences of F and F+-centers in TLD-500 detectors

The photoluminescence spectra of TLD-500 detectors were measured before and after γ-irradiation in the 1-50 Gy range. After irradiation, the PL spectrum at the excitation with Eexc = 4.8 eV features an additional wide band with the maximum at 550 nm associated with the formation of aggregate F22+-centers. The intensity of the emission of this band increases with a growing dose. Dependences of the intensities of emission of F and F+-centers on the dose was studied. A big difference in radiation-induced transformation of these centers is caused by competition of the processes of creation of aggregate centers and interconversion (F ↔ F+).