PSI - Issue 66

4

Author name / Structural Integrity Procedia 00 (2025) 000–000

Martha Dima et al. / Procedia Structural Integrity 66 (2024) 153–160

156

3. Results and Discussion Figures 2 and 3 show the variation of the produced voltages, from the examined GAGG-45 and GAGG-49 crystals, after the reading of the PMT signal. The threshold voltage of the electrometer was set up to 1Vpp. with exposure time and temperature. All curves are within the examined temperature range (23-157 o C) . The curves presented in Figs.2 and 3 indicate the light produced by the GAGG-45 and GAGG-49 crystals, during their irradiation with the 90 kVp X-rays. The pulses produced during the irradiation show initially a sharp increase, followed by a plateau and finally a sharp decrease of the signal.

Fig. 2. Normalized voltage for the GAGG-45 crystal, versus temperature and exposure time.