Abstract
A new resolved resonance region evaluation of 63Cu and 65Cu was done in the energy region
from 10-5 eV to 99.5 keV. The R-Matrix SAMMY method using the Reich-Moore approximation
was used to create a new set of consistent resonance parameters. The new evaluation was based
on three experimental transmission data sets; two measured at ORELA and one from MITR, and
two radiative capture experimental data sets from GELINA. A total of 141 new resonances were
identi ed for 63Cu and 117 for 65Cu. The corresponding set of external resonances for each isotope
was based on the identi ed resonances above 99.5 keV from the ORELA transmission data. The
negative external levels (bound levels) were determined to match the di erential thermal cross
section measured at the MITR. Double di erential elastic scattering cross sections were calculated
from the new set of resonance parameters. Benchmarking calculations were carried out on a set of
ICSBEP benchmarks. This work is in support of the DOE Nuclear Criticality Safety Program.
