Interpretation of the ASPIS Iron 88 programme with TRIPOLI-4® and quantification of uncertainties due to nuclear data

Abstract The ASPIS Iron 88 campaign performed in the NESTOR facility studied deep neutron propagation in mild steel. Several plates of 5 cm thickness were used as a neutron shielding next to a fission plate. Gold, indium, rhodium, sulphur and aluminium detectors, positioned between two consecutive steel plates, were used. This experiment is interpreted with the TRIPOLI-4® Monte-Carlo code, using the JEFF-3.1.1 and JEFF-3.2 nuclear data libraries. The ENDF/B-VIII.0 and JENDL-4.0 evaluations for iron 56 were also used for comparison. Results show good agreement between the calculation and the experiment for all detectors but the sulphur one. An attempt to calculate sensitivities and uncertainties to nuclear data was made with both the ERANOS deterministic code and TRIPOLI-4®. The results show that these uncertainties increase with the threshold of the studied reaction, reaching more than 30% for the sulphur detector.