PSI - Issue 66

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2025) 000–000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 66 (2024) 153–160

8th International Conference on Crack Paths Influence of temperature on the luminescence output of two GAGG:Ce single crystals scintillators Martha Dima* a , Ioannis Valais a , Dionysios Linardatos a , Nektarios Kalyvas a , George Fountos a , Athanasios Bakas b , Konstantinos Ninos b , Ioannis Kandarakis a and Christos Michail a,* a Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, Department of Biomedical Engineering, University of West Attica, Agiou Spyridonos, Athens 12210, Greece b Department of Biomedical Sciences,University of West Attica, Agiou Spyridonos, Athens 12210, Greece Abstract The aim of this study was to examine the influence of temperature rise on the luminescence efficiency of two Gd ₃ Al ₂ Ga ₃ O ₁₂ (GAGG:Ce) single crystals. The first sample (GAGG-45) has fast decay (<50 ns) and a light yield (LY) of 45000 photons/MeV whereas the second (GAGG-49) has a balanced decay (<90 ns) and a LY of 49000 photons/MeV. For the sample’s irradiation, under different temperature conditions (23-157 o C), a medical X-ray source (CPI-CMP 200 DR) was set to fixed high voltage (90kVp). The luminescence efficiency (LE) of both GAGG:Ce samples was found to decrease constantly with increasing temperature from 28.85 EU (28.5 o C) to 18.30 EU (150 o C) for the GAGG-45 crystal and from 32.33 EU (29.5 o C) to 18.85 EU (157 o C) for GAGG-49 crystal, respectively. Knowledge of the thermal behavior of modified single-crystal’s lattice structure, such as the two GAGG:Ce’s (45 and 49) could be useful, either for the temperature optimization in controlled environmental conditions, or for choosing between fast decay and light yield for other applications, such as medical imaging detectors. © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2024 Organizers Keywords: Single crystals; GAGG:Ce; Thermal behavior; extreme environments; medical imaging © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2024 Organizers

* Corresponding author.. E-mail address: cmichail@uniwa.gr

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2024 Organizers

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of CP 2024 Organizers 10.1016/j.prostr.2024.11.065