Comparison of active interrogation techniques

Active interrogation is necessary to detect highly enriched uranium in large cargo containers and trucks. To achieve sufficient penetration, most nuclear techniques first interrogate an object with high-energy photons or neutrons, to produce fission in any highly enriched uranium that may be present, and then detect the gamma rays or neutrons that are produced. Pulsed beams allow the detection of delayed gamma rays or neutrons from fission products between pulses. Many different systems have been proposed recently. This report presents the results for several techniques, both from measurements and from extensive simulations with the MCNPX code