Speaker
Description
Beryllium oxide (BeO) has gained increasing attention due to its strong optically stimulated luminescence (OSL) properties, tissue equivalence, ease of readout and favourable response across a wide energy range (30 keV – 6 MeV). However, BeOSL performance in the high-energy range requires further validation to ensure measurement accuracy in high-energy radiation fields. This study evaluates the in-beam response of BeOSL dosimeters when irradiated with MeV photon and electron beams used in external radiotherapy. Measurements were performed at Colțea Clinical Hospital using a Siemens Mevatron Primus linear accelerator. The dosimeters were irradiated within a 1-20 Gy dose range, using 6 MeV and 15 MeV photon beams and 5-12 MeV electron beams. The analysis focused on assessing dose-response linearity and energy dependence. In addition, an Advanced Markus electron chamber was used, providing a reference measurement. For comparison, passive thermoluminescent detectors (TLD), type LiF:Mg,Cu,P – GR200A, and silver halide film detectors (enclosed in dosimetric badges with metallic filters of different thicknesses) were irradiated under identical conditions. Gafchromic EBT4 films were also used to provide further cross-validation of the measured dose distributions. These findings contribute to the characterization of BeOSL dosimeters in high-energy radiotherapy beams, supporting their use as a reliable tool for medical dosimetry and other high-energy and high dose rate fields, such as those specific to classical or laser-driven accelerators.