Analyzing gamma irradiated spectrolite in relation to the photo-transfer TL and OSL effects

Abstract

Thermoluminescence (TL) and optically stimulated luminescence (OSL) are two techniques based on the luminescence phenomenon. They can be applied to study the response of materials that exhibit the property of emitting light after irradiation followed by a subsequent stimulus, which may be thermal (in the case of TL) or optical (in the case of OSL). These materials may also exhibit a phototransfer effect in their response, which can be observed through thermoluminescence phototransfer (PTTL) and optically stimulated luminescence phototransfer (PTOSL). The purpose of this work was to verify the presence of PTTL and PTOSL responses in Spectrolite after gamma irradiation from a ^60Co source and illumination with LEDs emitting in the ultraviolet region, aiming at its application in gamma radiation dosimetry. To this end, the signal from Spectrolite samples was studied through their TL/PTTL and OSL/PTOSL responses in three steps: (1) irradiation and measurement of TL and OSL responses; (2) irradiation, post-irradiation thermal treatment (PITT), and measurement of TL and OSL signals; and (3) irradiation, PITT, illumination with LEDs, and measurement of PTTL and PTOSL signals. The results showed the presence of a phototransfer effect in the PTTL response, but not in the PTOSL response. This finding indicates the need for further studies to evaluate the PTTL and PTOSL responses under different illumination wavelengths and exposure times. Additional investigations are therefore necessary to assess the suitability of this material for gamma radiation dosimetry.