On ⁵⁴Fe neutron cross section importance in iron

Area of Science:

• Nuclear Physics
• Neutron Cross-Section Evaluation
• Nuclear Data Libraries

Background:

• Accurate nuclear data is crucial for nuclear applications.
• The role of 54Fe isotopes in iron's nuclear properties requires detailed investigation.
• Existing nuclear data libraries may contain discrepancies affecting simulations.

Purpose of the Study:

• To assess the significance of 54Fe neutron cross-section (XS) data.
• To compare experimental measurements with nuclear data library evaluations.
• To identify discrepancies in 54Fe(n,p) and 54Fe(n,α) reaction rates and neutron leakage spectra.

Main Methods:

• Experimental measurement of reaction rates for 54Fe(n,p) and 54Fe(n,α).
• Measurement of fast neutron leakage spectra from a 100cm iron sphere using a stilbene scintillation detector.
• Sensitivity analysis of cross-section data.
• Utilized a Californium-252 (Cf-252) neutron source.

Main Results:

• Notable discrepancies were observed in the 54Fe(n,α) reaction rates across different nuclear data libraries.
• Fast neutron leakage spectra showed significant variations between libraries.
• The ENDF/B-VII.1 library demonstrated good agreement for leakage spectra in the 3.5-7.0 MeV region.
• CIELO and JEFF-3.2 libraries showed underestimation and overestimation, respectively, for leakage spectra.

Conclusions:

• The study highlights significant discrepancies in 54Fe nuclear data, particularly for the (n,α) reaction.
• Experimental validation is essential for refining nuclear data libraries.
• ENDF/B-VII.1 shows promise for specific energy regions, but further improvements are needed for other libraries like CIELO and JEFF-3.2.