Calculations of Induced Activity in the ATLAS Experiment for Nuclear Waste Zoning.

Extensive calculations were performed with the general activation formula using the fluxes of high-energy hadrons and low-energy neutrons previously obtained from simulations with the GCALOR code of the ATLAS detector. Three sets of proton cross-sections were used for hadrons energy above 20 MeV: (a) one set calculated with the YIELDX code (i.e., the Silberberg-Tsao formula of partial proton spallation cross-sections), (b) one set calculated with the Rudstam formula, and (c) the âbest-estimate' dataset which was a compilation of the available experimental and calculated data. In the energy region below 20 MeV, neutron activation cross-sections were taken from evaluated nuclear data files. The activity of each nuclide for a predefined operation scenario (i.e., number and duration of irradiation and shutdown cycles) was normalized to reference values taken from the European or Swiss legislations, to obtain an aggregate estimate of the radiological hazard comparable with a nuclear waste zoning definition criteria that has been adopted by the LHC experiments. The impact of changing the operation scenario and hadrons spallation cross-sections datasets on the zoning was investigated for the 21 most common materials