{'fraction_non_alphanumeric': 0.033777777777777775, 'fraction_numerical': 0.016, 'mean_word_length': 4.519607843137255, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 3, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Preliminary Studies of a Compact VHEE Linear Accelerator System for FLASH Radiotherapy

The FLASH Radiotherapy is a revolutionary new technique in the cancer cure: it spares healthy tissue from the damage of the ionizing radiation maintaining the tumor control as efficient as in the conventional radiotherapy. To allow the implementation of the FLASH Therapy concept into actual clinical use, it is necessary to have an accelerator able to deliver high dose per pulse (>1-2 Gy) in very short time pulse duration (μs) and high dose rate (> 106 Gy/s). Today, low energy (up to 7 MeV) S-band LINACs are being used in radiobiology and pre-clinical applications. However, in order to treat deep tumors the energy of the electrons should achieve the range of 50-250 MeV [1,2]. In this paper we address the main issues in the design of a compact C band (5.712 GHz) Very High Electron Energy (VHEE) for FLASH Radiotherapy. We present preliminary studies of a C-band system done at La Sapienza and INFN, aiming to reach a high accelerating gradient and high current necessary to deliver a dose >1 Gy/pulse, within a beam pulse of μs.