Neutronics and activation calculation for ITER generic site safety report

This paper focuses on some of the response functions obtained from a Sn radiation transport and activation analysis, namely the nuclear heating, decay heat and clearance index due to the neutron irradiation in the International Thermonuclear Experimental Reactor (ITER) fusion machine. The neutron and gamma flux spectra were calculated using the Scale 4.4a transport sequence Bonami-Nitawl-Xsdnrpm with a new 175n–42γ-coupled library (Vitenea-J) based on FENDL/E-2 data. The neutron and gamma heat deposition were evaluated using Kerma factor libraries based on EFF-2.4 data. The easy-99 and, for quality assurance purpose, the anita-2000 code packages were used to obtain the activation characteristics of all the materials/zones of ITER. They include the specific activity, decay heat, contact dose, clearance index, list of isotopes at shutdown and dominant isotopes versus cooling time, related to each material. A total neutron fluence of 0.5 MW-y/m2 at the outboard equator was considered. All the radiation transport and the easy-99 activation results were provided to ITER Joint Central Team and they were used for the ITER Generic Site Safety Report (GSSR). This paper shows the relevant heat deposition results obtained from the radiation transport analysis and the activation characteristics (decay heat and clearance index) calculated with anita-2000. A comparison with the easy-99 results is also given. The discrepancies between the two activation codes are lower than 1%.