Range Modulator and Neutrons in Particle Therapy with Protons

FLASH irradiation is considered a promising method for significantly sparing healthy tissue during irradiation with high-energy ionizing radiation without impairing the effect on the tumor tissue. With the currently possible implementation of FLASH irradiation with protons or 12C ions, fragmentation produces neutrons, whose dose contribution in the patient in combination with the high biological effectiveness of the neutrons leads to a non-negligible risk of secondary malignancies. The extent of neutron exposure associated with the bolus material for the patient is currently unclear and must be investigated further for clinical use. Neutron local dose distributions and energy spectra are measured using thermoluminescence dosimetry and novel scintillation detectors. The data obtained will serve as a benchmark for Monte Carlo simulations to reliably determine the neutron exposure during FLASH irradiation with protons.

The project will thus assist in the more precise determination of neutron exposure during FLASH irradiation and in the development of solutions to reduce associated risks. The aim is the Monte-Carlo-based and experimental determination of neutron contamination during FLASH irradiations as well as the further development of neutron measurement technology. This approach enables the optimization of safety and effectiveness in FLASH irradiation, as well as the acquisition of important insights for further development in this area.