Inspection techniques based on neutron interrogation

Nuclear based techniques, and among them the neutron based ones, provide two essential ingredients for effective substance detection, ability to detect and recognize as many signatures of the relevant chemical elements as possible (i.e., high specificity) and to do it on as small as possible volume of the interrogated object (i.e., imaging capabilities). Various techniques and their imaging capabilities, implementation and proper applications are reviewed. Active techniques based on thermal neutron capture (TNA) and fast neutron (mostly) inelastic scattering in various temporal regimes: steady state, slow (microsecond) and fast (nanosecond) pulsing is reviewed. Neutron resonance attenuation (NRA) based techniques also are discussed and evaluated within the envelope of existing and future applications.