Abstract
Irradiation of 237Np-bearing targets in the permanent beryllium reflector (PBR) of Oak Ridge National Laboratory’s (ORNL) High Flux Isotope Reactor (HFIR) results in high-purity 238Pu that can be used as a reliable power source for deep space and planetary National Aeronautics and Space Administration missions. However, HFIR’s 238Pu production capability is constrained by the available irradiation volume in its PBR. In preparation for the HFIR beryllium change-out in 2023, ORNL staff have redesigned the PBR to include six additional irradiation sites, be more versatile with respect to irradiation and scattering experiments, and enhance its thermal-structural performance. The new PBR design offers large potential increases in annual 238Pu production at ORNL.