Investigation on the mechanism underlying UV-induced reductions in radiophotoluminescence and electron spin resonance signals in Ag-doped alkali phosphate glass

AIM: Ag-doped sodium aluminophosphate glass (FD-7) is extensively used in dosimeters with the use of radiophotoluminescence (RPL). Recently, Ag-doped alkali phosphosilicate glass (SAPANS) has been developed as a new RPL dosimeter to overcome the low weather resistance of FD-7. However, the mechanisms of RPL center bleaching by long-term UV irradiation in SAPANS remain unclear. PURPOSE: In this study, the decay property of RPL centers in SAPANS under long-term ultraviolet (UV) exposure was investigated and compared with that in FD-7 to advance the understanding of the RPL emission mechanism. METHODS: ) in FD-7 and SAPANS samples irradiated with γ-rays and X-rays. In addition, the RPL and ESR intensities were analyzed as a function of UV exposure time using a multicomponent exponential decay function. RESULTS: in FD-7 and SAPANS. Moreover, the existence of a new RPL center exhibiting a slow response to UV exposure in FD-7 and SAPANS was suggested. CONCLUSIONS: We successfully elucidated the RPL characteristics of SAPANS under long-term UV exposure. The results of this study provide new insights into the RPL centers of not only SAPANS but also various Ag-doped RPL glasses.