On the evaluation of 23Na neutron-induced reactions and validations

Abstract New recommendations for neutron-induced reactions on 23 Na are presented for incident energies from thermal to 200 MeV including resonance parameters up to 1 MeV, and covariance files in the resonance and fast neutron regions. Calculations are based on the nuclear reaction code TALYS and covariances in the fast neutron range are obtained with a Monte Carlo approach. Discrepancies between experimental data and evaluations are presented, indicating needs for new measurements. Validations with integral benchmarks and a simplified model of the Kalimer-600 Sodium Fast Reactor are presented with a special emphasis on the void coefficient, including its uncertainty assessment. Finally, conclusions on the state of knowledge of neutron induced reactions on sodium are presented with recommendations for new measurements.