Newly Evaluated Neutron Reaction Data on Chromium Isotopes

Abstract

Neutron reaction data for the set of major chromium isotopes were reevaluated from the thermal energy range up to 20 MeV. In the low energy region, updates to the thermal values together with an improved $R$-matrix analysis of the resonance parameters characterizing the cluster of large $s$-wave resonances for ${}^{50,53}$Cr isotopes were performed. In the intermediate and high energy range up to 20 MeV, the evaluation methodology used statistical nuclear reaction models implemented in the EMPIRE code within the Hauser-Feshbach framework to evaluate the reaction cross sections and angular distributions. Exceptionally, experimental data were used to evaluate relevant cross sections above the resonance region up to 5 MeV in the major ${}^{52}$Cr isotope. Evaluations were benchmarked with Monte Carlo simulations of a small suite of critical assemblies highly sensitive to Chromium data, and with the Oktavian shielding benchmark to judge deep penetration performance with a 14-MeV D-T neutron source. A significant improvement in performance is demonstrated compared to existing evaluations.

arXiv commentSubmitted to Nuclear Data Sheets. 41 pages, 44 Figures, 13 Tables

References in corpus (5)

• The Experimental Nuclear Reaction Data (EXFOR): Extended Computer Database and Web Retrieval System
• IRDFF-II: A New Neutron Metrology Library
• Higher-spin Chern-Simons theories in odd dimensions
• Direct Neutron Capture for Magic-Shell Nuclei
• Constraining level densities through quantitative correlations with cross-section data

Cited by in corpus (3)

• A novel Machine-Learning method for spin classification of neutron resonances
• Evaluation of ${}^{86}$Kr Cross Sections For Use in Fusion Diagnostics
• New measurement of ${}^{50}$Cr and ${}^{53}$Cr (n,$\gamma$) cross sections at n_TOF: a call for chromium nuclear data revision