A FEASIBILITY STUDY OF CODED-APERTURE IMAGING AND 3D-DIV FOR NUCLEAR MATERIALS ACCOUNTANCY IN ENRICHMENT PLANTS

Acollaborative effort has been established to investigate the use of a three-dimensional laser imaging system combined with gamma imaging systems for international safeguards applications. The effort is being conducted by Oak Ridge National Laboratory (ORNL), Lawrence Berkeley National Laboratory, Lawrence Livermore National Laboratory, the Joint Research Centre at Ispra, Italy and Brazilian-Argentine Agency for Accounting and Control of nuclear materials. This paper presents a feasibility study of coded-aperture imaging for nuclear materials accountancy in enrichment plants. Specifically, measurements were performedwith an extant imager prototypeat the ORNL Safeguards Laboratory using uranium standards that model nuclear holdup in process equipment. The measurements showed that for gram quantities of uranium at a standoff distance of ~4 m, the imager was able to predict source location and geometry with good accuracy during integration times ~1 h. The imager prototype, preliminary measurements of gaseousUF6, and the merits of coded-aperture imaging for nuclear materials accountancy are also discussed.