New neutron cross-section measurements at ORELA and their application in nuclear criticality calculations

Many older neutron cross-section evaluations from libraries such as ENDF/B-VI or JENDL-3.2 show deficiencies in energy ranges that are important for criticality safety applications. Consequently, these evaluated data may not be adequate for nuclear criticality calculations where effects such as self-shielding, multiple scattering, or Doppler broadening are important. To support the Nuclear Criticality Safety Program, neutron cross-section measurements have been initiated at the Oak Ridge Electron Linear Accelerator (ORELA). ORELA is ideally suited to measure fission, neutron total, and capture cross-sections in the energy range from 1 eV to ∼600 keV, which is important for many nuclear criticality safety applications.