A novel approach with quadrupole magnets for precise deflection, scattering and focusing of very high energy electron beams (VHEE)

Abstract

A novel approach involving quadrupole magnets has been proposed to deflect and disperse electrons in the irradiation fields, as well as a system for focusing beams at specific depths. This research also presents a comparison between VHEE and conventional radiotherapy, supported by the validation of our Monte Carlo simulations using real measurement data for low-energy electrons (6, 9 and 15 MeV) in water and air, thus ensuring the reliability of our results. Simulations demonstrate high accuracy, with agreement with measurement data of up to 0.58 % and less than 1.86 % for all validated energies and fields. The results show a significant reduction in entrance dose (82.4 %) with focused beams compared to unfocused beams, as well as a 17.6 % reduction at a depth of 30 cm. The study of the spread electron peak (SOEP) for 4 focused beams varies in magnetic field intensity to cover a depth of 11 cm–18 cm, with an entrance dose at a depth of 0.5 mm of 27.15 % and 24.5 % of the exit dose at a depth of 40 cm. The VHEEs also offer the advantage of low Linear Energy Transfer (LET) compared with protons, which reduces the risk of damage several times over. • MC-Validation shows high agreement with experimental measurements. • Focused VHEE reduces entrance dose by 82.4 % and exit dose by 17.6 %. • The quadrupole used shows high precision in scattering and focusing the dose. • The magnetic field required to deflect electrons lower than protons. • The High-energy electrons have a low LET compared with protons.