Secondary Radiation During 7Li Irradiation of a PMMA Phantom

Introduction The recently initiated ENVISION project inter alia aims at the development of in-beam dose verification systems based on promptly occurring secondary radiation during ion beam cancer irradiation. Especially a Compton camera system design will be studied. An important parameter for the optimization of such a system is the energy distribution and the fluence rate of the photon radiation field lateral to the irradiated volume. Additionally, the background due to the neutron component has to be scrutinized. In preparation of further experiments and simulations the lateral radiation field of a phantom irradiated with carbon and lithium ions has been probed with two detector modules that were developed for photon detection within a narrow field of view.