Radiation therapy is currently the most utilized technique for the treatment of tumors by means of ionizing radiation, such as electrons, protons and x/gamma rays, depending on the type, size and depth of the cancer mass. Radiation therapy has in general fulfilled the main requirement of targeting thus damaging the malignant cells and sparing the healthy tissues as best as possible. In this scenario, electron linear accelerators have been operated as viable tools for the delivery of both high-energetic electrons and x-ray beams, which are obtained via the bremsstrahlung process of the electrons hitting on a high-Z material. Recently, it has been experimentally demonstrated that ultrahigh dose-rate bursts of electrons and x-ray beams increase the differential response between healthy and tumor tissues. This beneficial response is referred to as the FLASH effect. For this purpose, we have developed the first dedicated compact $S$-band linear accelerator for FLASH radiotherapy. This linac is optimized for a nominal energy of 7 MeV and a pulsed electron beam current of 100 mA and above. The accelerator is mounted on a remote-controlled system for preclinical research studies in the FLASH regime. We will show the rf and beam dynamics design of the $S$-band linac as well as the commissioning and high-power rf tests. Furthermore, the results of the dosimetric measurements will be illustrated.

中文翻译：

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CompactS-band线性加速器系统，用于超快，超高剂量率放疗

目前，放射疗法是通过电离辐射（例如电子，质子和X /γ射线）来治疗肿瘤的最常用技术，具体取决于癌症块的类型，大小和深度。放射疗法通常已经满足了靶向的主要要求，从而尽可能地损害了恶性细胞并保护了健康组织。在这种情况下，电子线性加速器已被用作传递高能电子和X射线束的可行工具，这是通过电子撞击a Z材料的the致辐射过程获得的。最近，已经通过实验证明，电子和X射线束的超高剂量率爆发会增加健康组织和肿瘤组织之间的差异反应。这种有益的响应称为“闪光效应”。为此，我们开发了第一个专用契约$\mathrm{小号}$带线性加速器，用于FLASH放射治疗。该直线加速器针对7 MeV的标称能量和100 mA及更高的脉冲电子束电流进行了优化。该加速器安装在远程控制系统上，用于FLASH模式下的临床前研究。我们将展示射频和光束动力学设计$\mathrm{小号}$带直线加速器以及调试和大功率射频测试。此外，将说明剂量测定的结果。