Multidetector analysis system

The multidetector analysis system (MDAS) is a new approach to the nondestructive analysis (NDA) of fissile and other radioactive material. The system uses multiple detectors of two different types to determine fissile isotopic content and quantity present in entire reactor fuel assemblies or waste drums measured by the system. The methods used in MDAS include coincidence spectroscopy with large detector arrays, coincidence gating, list-mode data acquisition, fast liquid scintillators, and pulse-shape discrimination. Although, MDAS relies on the fundamental physics and fast coincidence detection methods used by the nuclear and high-energy research communities, this application of determining the ratios of fissile isotopes is unique to this system and has been patented. Development of MDAS has been supported primarily by the US Department of Energy (DOE) spent nuclear fuel program. Characterization of spent reactor fuel, transuranic waste, and other fissile material is becoming increasingly important for environmental cleanup and weapons safeguards. Traditional radioanalysis measurements that relied on sampling and destructive analysis methods are less practical than they once were because of closing of facilities and hot cells. Traditional NDA measurements, which primarily treated radiation as a continuous emission of energy, are also becoming obsolete as spectral information is required for the mostmore » detailed characterization.« less