Time of Flight Associated Particle Imaging with Neutron Induced Gamma-rays*

Lawrence Livermore National Laboratory and Oak Ridge National Laboratory are incorporating neutron-induced gamma rays from a time of flight associated particle imaging (API) D-T neutron generator to build a new portable detection system capable of both transmission and backscattering imaging of objects potentially containing nuclear fissionable materials. This talk describes the current efforts to develop and test this new API based detection system. Preliminary results from the testing of hardware upgrades to the detection system, which include new pulse shape discriminating (PSD) plastic scintillators and a high-throughput data acquisition system, will be presented. Image reconstruction techniques using spectral, neutron-gamma correlation, and neutron fission multiplicity simulations to characterize the object's depth, composition and inner void spaces will also be discussed.