sup 56 Fe resonance parameters for neutron energies up to 850 keV

Technical Report · Sat Dec 01 04:00:00 EST 1990

DOI:https://doi.org/10.2172/6028649· OSTI ID:6028649

Perey, C M; Perey, F G; Harvey, J A; Hill, N W; Larson, N M

High-resolution neutron measurements for {sup 56}Fe-enriched iron targets were made at the Oak Ridge Electron Linear Accelerator (ORELA) in transmission below 20 MeV and in differential elastic scattering below 5 MeV. Transmission measurements were also performed with a natural iron target below 160 keV. The transmission data were analyzed from 5 to 850 keV with the multilevel R-matrix code SAMMY which uses Bayes' theorem for the fitting process. This code provides energies and neutron widths of the resonances inside the 5- to 850-keV energy region, as well as possible parameterization for resonances external to the analyzed region to describe the smooth cross section from a few eV to 850 keV. The resulting set of resonance parameters yields the accepted values for the thermal total and capture cross sections. The differential elastic-scattering data at several scattering angles were compared to theoretical calculations from 40 to 850 keV using the R-matrix code RFUNC based on the Blatt-Biedenharn formalism. Various combinations of spin and parity were tried to predict cross sections for the well defined {ell} > 0 resonances; comparison of these predictions with the data allowed us to determine the most likely spin and parity assignments for these resonances. The results of a capture data analysis by Corvi et al. (COR84), from 2 to 350 keV, were combined with our results to obtain the radiation widths of the resonances below 350 keV observed in transmission, capture, and differential elastic-scattering experiments.

• Research Organization: Oak Ridge National Lab., TN (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6028649
• Report Number(s): ORNL/TM-11742; ON: DE91007826
• Country of Publication: United States
• Language: English

Related Subjects

651420* -- Nuclear Properties & Reactions
A=20-38
Experimental
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BARYON REACTIONS
CAPTURE
CROSS SECTIONS
DATA
DATA ACQUISITION
ELASTIC SCATTERING
ENERGY DEPENDENCE
ENERGY RANGE
EXPERIMENTAL DATA
FUNCTIONS
HADRON REACTIONS
INELASTIC SCATTERING
INFORMATION
IRON 56 TARGET
KEV RANGE
MATRICES
NEUTRON REACTIONS
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUMERICAL DATA
R MATRIX
RESONANCE SCATTERING
SCATTERING
STRENGTH FUNCTIONS
TARGETS