ANTONIO, PATRICIA L.CALDAS, LINDA V.E.2024-03-222024-03-22ANTONIO, PATRICIA L.; CALDAS, LINDA V.E. Phototransferred thermoluminescence in commercial dosimeters after exposure to beta radiation: PTTL signal as a function of variation of the illumination time and wavelength. In: INTERNATIONAL CONFERENCE ON SOLID STATE DOSIMETRY, 20th, September 17-22, 2023, Viareggio, Italy. <b>Abstract...</b> Disponível em: https://repositorio.ipen.br/handle/123456789/47978.https://repositorio.ipen.br/handle/123456789/47978Radiation dosimetry allows the analysis of the energy deposited in a material to evaluate the effect caused on this material; it can be done using different radiation detectors, and there are several dosimetric materials that can be employed, according to the radiation kind and the purpose of its application. A material can only be considered a radiation dosimeter if it presents certain conditions; for dosimeters that present luminescent response, it is necessary to present specific characteristics in this luminescence signal. However, there are ways to study the signal to allow the response obtained to provide these characteristics, for example, studying the phenomenon of phototransfer of the luminescent signal of a material. The main objective of this work was to analyze the occurrence of phototransfer on the thermoluminescence (TL) of different commercial dosimeters, the phenomenon of the phototransferred TL (PTTL). For this, the TL and PTTL responses of LiF:Mg,Ti (TLD-100), CaF2:Dy (TLD-200), CaF2:Mn (TLD-400) and CaSO4:Dy (TLD-900) dosimeters were investigated using the 90Sr+90Y source of the TL/OSL reader system Risø. During the TL/PTTL measurements, performed with the same reader, the maximum temperatures were 350°C (TLD-200), 400°C (TLD-100 e -900) e 450°C (TLD-400), and the heating rate was kept constant at 10°C/s. The first step was to verify the TL response of the materials, by means of the TL emission curves after irradiation (with absorbed doses of 0.7 Gy for TLD-100 and TLD-900, 20 Gy for TLD-200 and 50 Gy for TLD-400). The main peaks were observed at the temperatures of 252°C for TLD-100, 312°C for TLD-200, 398°C for TLD-400 e 226°C for TLD-900. The second step was to analyze the TL response after irradiation and a thermal treatment post-irradiation (TTPI) of 280°C/15 min for TLD-100 e TLD-900, 300°C/15 min for TLD-200 and 400°C/15 min for TLD-400; the highest TL emission occurred at 362°C (TLD-100), 139°C (TLD-200), 398°C (TLD-400) and 397°C (TLD-900). The third step was the verification of the PTTL signal, obtained after irradiation, TTPI and illumination (with UV leds) of the materials at the conditions of 265 nm/5 min for TLD-100 and 365 nm/5 min for TLD-200, TLD-400 e TLD-900. For TLD-100, a PTTL signal was verified, because two new peaks emerged at 133°C and 261°C; for TLD-200 and TLD-400 no PTTL signal was observed; for TLD-900 it was possible to obtain a PTTL response once a peak appeared at 197°C, which did not exist after irradiation and TTPI (second step). In order to continue studying the PTTL signal, this response was verified varying the illumination time for the four materials between 2.5 min and 25 min. The PTTL response maximum was observed for 15 min illumination for all the materials. The PTTL was also studied in function of the wavelength for 265 nm, 310 nm, 365 nm, 400 nm e 420 nm; the results showed that the most intense signal occurred at 265 nm for TLD-100, -400 and -900, and 365 nm for TLD-200.openAccessPhototransferred thermoluminescence in commercial dosimeters after exposure to beta radiationResumo de eventos científicoshttps://orcid.org/0000-0002-7362-2455