Portable, High Resolution, Combined Neutron/X-ray Imaging System

NNSA plays a vital role in the U.S. government’s efforts to prevent, respond to, and counter terrorists or other adversaries with a nuclear or radiological device. High resolution neutron/Xray radiography imagers are critical to effectively accomplish this goal. Xray sources needed for the task are readily available and fast neutron sources with high flux that meet the SWaP requirements are being developed. Unfortunately, detectors that are simultaneously sensitive to fast neutrons and high energy Xrays and can generate high resolution images in short time duration, do not exist. We are addressing this specific need. The proposed research directly addresses the DOE/NNSA’s mission needs with the development of a portable, high spatial resolution, combined neutron/ Xray radiography detector. The envisioned detector would be capable of high sensitivity, high resolution, imaging of fast neutrons and high energy Xrays. The detector will employ a newly discovered, high performance, structured, solidstate sensor coupled to a large area readout to provide images in digital format. The Phase I research demonstrated feasibility of our approach through 1 sensor design and simulations, 2 fabrication of sensors and characterization studies, 3 assembling prototype detector and performing evaluations using fast neutrons and high energy Xrays, and 4 demonstrating high resolution imaging using MeV energy range neutrons and Xrays. We worked closely with the DOE program officials through periodic reviews for planning translation of this transformative technology into their application space. The goal of the Phase II is to develop a fully functional detector and conduct testing under realistic field conditions with the help from our ORNL collaborators. Specifically, we will develop protocols to manufacture large area sensors with the desired properties. This will be an iterative process involving simulations, fabrication, and characterizations. After preliminary tests at RMD, the sensors and the detector will be tested at ORNL using DD/DT generators and 7 MeV Xrays. A large area detector capable of high sensitivity, high spatial resolution for neutrons and X rays is needed for numerous applications in homeland security, nondestructive testing, and military hardware testing and will be an ideal solution for studying magnetic structures, phase transitions, disorder, and local structure phenomena in advanced materials. Research in each of these areas will directly benefit the public by accelerating the development of new drugs, novel materials, and systems, all of which have a direct impact on health care, quality of life, addressing the nation’s future energy needs, and it will expand our technology base.