Stilbene Array for Portable Neutron Imaging

Neutron detection and imaging technologies are critical for inspecting nuclear materials located inside containers. Applications in both nuclear material control and nonproliferation would benefit from detector materials with greater ability to distinguish neutron and gamma radiation and which also facilitate portable operation. The organic crystalline scintillator stilbene has long been recognized as an excellent material for detection of fast neutrons in a gamma-ray background, and has recently become commercially available. The primary advantages of stilbene are its high sensitivity to neutrons and superior separation of signals from neutrons and gamma rays. Additionally, stilbene is a solid-state, non- hazardous material and is suitable for use in portable detection equipment. To support applications requiring high- resolution portable neutron imaging, we propose developing standard and custom products based on a pixelated arrayof stilbene crystal elements. The objective of the proposed effort is to develop a robust process for fabricating stilbene pixels and assembling them into high-performance imaging arrays. In Phase I we will assemble suitable arrays using feedback from characterization and identify a path towards efficiency improvements and cost reduction. Processes for improvements will be implemented in Phase II to achieve a quality and price which is acceptable for integration into nuclear materials characterization systems. Improved capabilities for neutron imaging would impact national security by benefiting nuclear material control and accountability applications and nuclear nonproliferation applications. Other commercial applications exist in neutron radiography for non-destructive materials analysis.