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Initial Dosimetry of a Prototype Ultra-High Dose Rate Electron-Beam Irradiator for FLASH RT Preclinical Studies

  • Hyun Kim (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Heuijin Lim (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Sang Koo Kang (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Sang Jin Lee (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Tae Woo Kang (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Seung Wook Kim (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Wung-Hoa Park (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Manwoo Lee (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Kyoung Won Jang (Research Center, Dongnam Institute of Radiological and Medical Sciences) ;
  • Dong Hyeok Jeong (Research Center, Dongnam Institute of Radiological and Medical Sciences)
  • 투고 : 2023.08.08
  • 심사 : 2023.09.14
  • 발행 : 2023.09.30

초록

Purpose: FLASH radiotherapy (RT) using ultra-high dose rate (>40 Gy/s) radiation is being studied worldwide. However, experimental studies such as preclinical studies using small animals are difficult to perform due to the limited availability of irradiation devices and methods for generating a FLASH beam. In this paper, we report the initial dosimetry results of a prototype electron linear accelerator (LINAC)-based irradiation system to perform ultra-high dose rate (UHDR) preclinical experiments. Methods: The present study used the prototype electron LINAC developed by the Research Center of Dongnam Institute of Radiological and Medical Sciences (DIRAMS) in Korea. We investigated the beam current dependence of the depth dose to determine the optimal beam current for preclinical experiments. The dose rate in the UHDR region was measured by film dosimetry. Results: Depth dose measurements showed that the optimal beam current for preclinical experiments was approximately 33 mA, corresponding to a mean energy of 4.4 MeV. Additionally, the average dose rates of 80.4 Gy/s and 162.0 Gy/s at a source-to-phantom surface distance of 30 cm were obtained at pulse repetition frequencies of 100 Hz and 200 Hz, respectively. The dose per pulse and instantaneous dose rate were estimated to be approximately 0.80 Gy and 3.8×105 Gy/s, respectively. Conclusions: Film dosimetry verified the appropriate dose rates to perform FLASH RT preclinical studies using the developed electron-beam irradiator. However, further research on the development of innovative beam monitoring systems and stabilization of the accelerator beam is required.

키워드

과제정보

This work was supported by the Dongnam Institute of Radiological & Medical Sciences (DIRAMS) grant funded by the Korea government (The Ministry of Science and ICT) under Grant 50493-2023.

참고문헌

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