Associated particle imaging (API) is a fast-neutron reaction imaging system. An object is illuminated with 14-MeV neutrons and these neutron interaction sites are imaged. The T(d,n)[sup 4]He reaction is used to produce a neutron and an alpha particle which move apart in opposite directions. By detecting the alpha particle, the direction of travel of the neutron is known. When the neutron strikes any material (except hydrogen and helium) it causes the material to emit gamma radiation. If one of the gamma-rays is detected it is then known that a reaction has taken place. By measuring the time between alpha detection and gammadetection, it is known how long the neutron traveled before reacting. By constructing a tally (or histogram) of these reaction sites an image is constructed. By examining the gamma-ray spectra corresponding to each region of space, elemental analysis of that region can be performed. This technique and it's applications are discussed in this paper.

A fast-neutron-capture imaging system is being designed. 14.1 MeV neutrons will be produced with a sealed-tube neutron generator (STNG) via the t(d, n)4He reaction. The associated alpha particle will be imaged defining the neutron direction. The timing and energy of a neutron-inelastic-scatter gamma ray will define the source-to-target distance and the target isotope. A special sealed-tube neutron generator (STNG) has been designed. The performance of various components of the system has been measured or calculated, and the results are used to predict the overall performance of the system.