The International Atomic Energy Agency (IAEA) is the leading organization for monitoring nuclear facilities worldwide, and the Agency's inspection methods are constantly developing and improving in an effort to more effectively safeguard nuclear material. Advanced inspection techniques enable the inspectors to decrease the uncertainty in their measurements, which translates to smaller defects, or quantities of diverted material. However, one area that continues to be difficult for the IAEA is the non-invasive, in-core inspection of research reactors with the objective of verifying the quantity of different fissile isotopes. Recently, digital-imaging techniques for qualitative inspections of irradiated fuel using Cherenkov light measurements have advanced the Agency's ability to perform verification measurements following discharge of fuel from reactors. Unfortunately, these measurements are limited in their value for safeguards and nuclear material accountancy, since they do not quantify the fissile material quantities and cannot characterize a reactor during operations. This study seeks to leverage existing optical measurement methods by assembling a new detecting system, deemed the Cherenkov Radiation Assay for Nuclear Kinetics (CRANK) system, to identify and characterize Cherenkov light in an operating reactor, and to relate this signature to the quantity of fissile material in the reactor, ultimately allowing the IAEA to formulate a binary decision in the event of plutonium diversion. Differences in reactor kinetics parameters of specific fissile isotopes, such as uranium and plutonium, in a reactor facilitate the identification of the fuel composition by characterizing the response of the reactor during reactivity perturbations. The intensity of Cherenkov light emitted from a reactor is linearly proportional to changes in the reactor's power, and this is utilized to identify specific fuel signatures in the reactor by measurements of this light.
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