Abstract In this study, an electron-scattering device was fabricated to practically use the ultra-high dose rate electron beams for the FLASH preclinical research in Dongnam Institute of Radiological and Medical Sciences. The Dongnam Institute of Radiological and Medical Sciences has been involved in the investigation of linear accelerators for preclinical research and has recently implemented FLASH electron beams. To determine the geometry of the scattering device for the FLASH preclinical research with a 6-MeV linear accelerator, the Monte Carlo N-particle transport code was exploited. By employing the fabricated scattering device, the off-axis and depth dose distributions were measured with radiochromic films. The generated mean energy of electron beams via the scattering device was 4.3 MeV, and the symmetry and flatness of the off-axis dose distribution were 0.11% and 2.33%, respectively. Finally, the doses per pulse were obtained as a function of the source to surface distance (SSD); the measured dose per pulse varied from 4.0 to 0.2 Gy/pulse at an SSD range of 20–90 cm. At an SSD of 30 cm with a 100-Hz repetition rate, the dose rate was 180 Gy/s, which is sufficient for the preclinical FLASH studies.

中文翻译：

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用于 6-MeV LINAC FLASH 临床前研究的电子束散射装置

摘要 在这项研究中，制造了一种电子散射装置，以实际使用超高剂量率电子束，用于东南放射医学科学研究所的 FLASH 临床前研究。东南放射医学科学研究所一直参与用于临床前研究的直线加速器的研究，并最近实施了 FLASH 电子束。为了使用 6-MeV 直线加速器确定用于 FLASH 临床前研究的散射装置的几何形状，利用了蒙特卡罗 N 粒子传输代码。通过使用制造的散射装置，用放射致变色薄膜测量离轴和深度剂量分布。通过散射装置产生的电子束平均能量为 4.3 MeV，离轴剂量分布的对称性和平坦度分别为0.11%和2.33%。最后，作为源到表面距离 (SSD) 的函数获得每个脉冲的剂量；在 20-90 cm 的 SSD 范围内，测量的每脉冲剂量从 4.0 到 0.2 Gy/脉冲不等。在 30 cm SSD 和 100 Hz 重复率下，剂量率为 180 Gy/s，足以用于临床前 FLASH 研究。