Speaker
Description
To support the establishment of a future 30–70 MeV proton irradiation facility and to facilitate experiment planning for semiconductor irradiation experiments and radiobiology studies, this work develops a beam evaluation framework that links beam characteristics to application-oriented irradiation conditions prior to facility operation. The framework establishes physical baselines by integrating range–energy relationships, material-dependent depth-dose behavior, and setup-related correction models.
A systematic database of depth-dose curves was generated using TOPAS, a Geant4-based Monte Carlo simulation platform, for proton beams in water, PMMA, copper, and graphite across the energy range of 20–70 MeV. The lower energy extension to 20 MeV supports validation with the existing infrastructure and enables the study of degraded beam conditions relevant to practical irradiation setups. Range-related beam parameters, including Bragg peak position, R80, practical range (Rp), and full width at half maximum (FWHM) of the Bragg peak, were extracted for evaluation purposes. To further establish physical consistency, simulated range-related results were compared with the NIST PSTAR projected range data and showed good agreement.
The reliability of the proposed framework was experimentally assessed using an existing 30 MeV proton beam and radiochromic EBT3 film measurements. Energy inferred from the measured range-related parameters through the proposed approach demonstrated good consistency for practical irradiation evaluation with values obtained from a multilayer Faraday cup, supporting the applicability of the evaluation framework.
In addition, an air-attenuation correction method was developed to account for energy loss during beam transport in air under different source-to-surface distances. The proposed framework provides a practical basis for reducing commissioning effort and supports predictive irradiation experiment design for future semiconductor and radiobiology applications.