ESTRO 2025 - Abstract Book

S2577

Physics - Detectors, dose measurement and phantoms

ESTRO 2025

During conventional radiotherapy tests, the THGEM detector exhibited a nearly linear response comparable to the PTW Farmer ionization chamber. It demonstrated a plateau phase about 400V operation, confirming its clinical reliability. Its unique micro-structure enables rapid signal response, making it highly suitable for direct measurement of Flash-RT accelerator beam structure. Compared with BET3 films, the detector maintained excellent linear dose response at dose rates as high as 250 Gy/s. Conclusion: With its distinct design and rapid response capability, the THGEM detector performs well in modern radiotherapy. It not only rivals traditional ionization chambers in standard treatments but also precisely measures doses in high dose rate Flash radiotherapy. This characteristic effectively addresses the limitations of conventional detectors, promoting the safety and efficiency of radiotherapy advancements.

Keywords: Flash-RT, Dose rate linearity, THGEM