Decommissioning of medical cylotrons: Case study: 40 MeV CGR Cyclotron VUB (Brussels)

A good characterization of the radionuclide inventory can be done with the computer codes validated with the experiments performed with less effort. 40 MeV cyclotron at Vrije Universiteit Brussel (VUB), which is a variable energy multi-particle cyclotron, is a case study for this thesis to obtain a reliable methodology based on computational tools and validate it with the available measurements. The Monte-Carlo burn-up code ALEPH2 developed at SCK CEN was used to determine the induced activities in the investigated materials that have measured activation values. In order to do the calculations, the main cyclotron room was modelled with the MCNP6 code. The special attention during this study was given on the operational workload of cyclotron that was in operation from 1985 till 2020. The workload was simplified in several approaches developed here either by grouping the particles, energies or irradiation time. Experimental data was used to determine the best approach that might be used in future for waste analysis needed for later decommissioning.