Proton FLASH Irradiation Platform for Small Animal Setup at Chang Gung Memorial Hospital

The purpose of this study was to create a platform for conducting small animal proton FLASH irradiation at a research-specific therapy center using an auxiliary proton beam line. A dose monitoring system was implemented to provide real-time irradiation dose and dose rate time structure information, utilizing a transmission ionization chamber (TIC), a plastic scintillator-based beam position monitor, and a poor man faraday cup (PMFC). Both the TIC and PMFC were equipped with a custom-made fast-reading current integral electronics device, allowing for real-time dose monitoring with a resolution of 0.5 ms. Experimental testing showed that the maximum dose that could be delivered to the target in a single pulse of 230-MeV protons was approximately 20 Gy, during a pulse period of 199 ms, at a dose rate of 100 Gy/s. The establishment of a dedicated proton research platform at Chang Gung Memorial Hospital has enabled investigation of the biological effects of FLASH irradiation on small animals. The final setup data serves as a useful reference for both planning future experiments and improving the facility for beam users. This study's achievement provides a valuable foundation for further research on proton FLASH irradiation, potentially offering new insights into its applications for cancer treatment.