Beam parameters optimization and characterization for a TUrning LInac for Protontherapy

Particle tracking and beam optics analysis on a toroidal gantry for proton therapy

GaToroid is a concept of toroidal gantry for hadron therapy under investigation at CERN It makes use of the toroidal magnetic field between each pair of coils to steer and focus the particle beams down to the patient. This peculiar concept requires detailed studies on particle tracking and beam optics to optimise the winding geometry and explore the properties of the system. The work presented in this manuscript is focused on the features of a GaToroid system for protons, specifically designed to minimise the footprint and weight of the gantry. Firstly, a two-dimensional single particle tracking was developed to optimise the coil geometry and the toroidal magnetic field, aiming to the maximisation of the energy acceptance of the magnet. Particles over the whole spectrum of treatment energy are directed at isocenter within 1 mm of precision. This procedure, restricted to the symmetry plane between each pair of coils, defines different beam orbits, function of the beam energy. Subsequently, a three-dimensional particle tracking was implemented to evaluate the interaction of a beam of finite dimensions with the complete magnetic field map in vacuum. The parameters of the simulated beam at the isocenter are coherent with the clinical requirements. The results of the three-dimensional tracking were then used to calculate the linear transfer matrix associated to each beam orbit. Finally, the option of performing the beam spot scanning at the isocenter by acting on the upstream steering magnet has been investigated, highlighting the potential of the concept, as well as the limitations related to the scanning field dimension and source-to-axis distance. In conclusion, the results described in this paper represent a crucial step toward the understanding of the beam optics properties of a GaToroid gantry.

FLUKA particle therapy tool for Monte Carlo independent calculation of scanned proton and carbon ion beam therapy

While Monte Carlo (MC) codes are considered as the gold standard for dosimetric calculations, the availability of user friendly MC codes suited for particle therapy is limited. Based on the FLUKA MC code and its graphical user interface (GUI) Flair, we developed an easy-to-use tool which enables simple and reliable simulations for particle therapy. In this paper we provide an overview of functionalities of the tool and with the presented clinical, proton and carbon ion therapy examples we demonstrate its reliability and the usability in the clinical environment and show its flexibility for research purposes. The first, easy-to-use FLUKA MC platform for particle therapy with GUI functionalities allows a user with a minimal effort and reduced knowledge about MC details to apply MC at their facility and is expected to enhance the popularity of the MC for both research and clinical quality assurance and commissioning purposes.