Neutron tomographic fissile assay in spent fuel using the lead slowing down time spectrometer

A tomographical fissile assay technique for light water reactor spent fuels was developed based on the lead slowing down time spectrometer (LSDTS). Th e Monte Carlo method was used for system performance and for simulation of the sensitivity of detection of fissile materials using neutron emission to mography. A typical spent PWR fuel element was simulated and the spatial an d mass sensitivity of the fissile components were investigated. From these studies, the LSDTS system is shown to be a very sensitive device for analyz ing the spatial distribution of total fissile materials of a spent fuel ass embly in a properly selected assay neutron energy range. This method is als o applicable to nuclear waste assay. (C) 2001 Elsevier Science B.V. All rig hts reserved.