Photon interrogation annual report for FY-1980

The Photon Interrogation Technique is being developed for the assay of transuranic materials. A description of source and detector geometry, die-away times and photon flux measurements is given. Considerable effort during FY-1980 was devoted to collimator construction and shielding materials and configurations. Boric acid was found to be a very efficient shielding material for this application. Descriptions and results of these efforts are presented. Results of photon flux determinations, system response to source position and their effects on accuracy are discussed. Changes in the detector system produced a considerable efficiency increase and instrumentation changes brought improved performance. The instrument system with additions can obtain neutron spectral information. A schedule for further development of the system is presented.