This Small Business Innovation Research Phase I project will develop the technology needed for high performance neutron detectors that use Ce3+ activated 6Li glass in the form of monodisperse microspheres with strategically controlled dimensions and architecture. Current Ce3+/6Li glass scintillator technology has the potential to produce neutron detectors that are extremely sensitive, rugged, flexible in design geometry, have a large dynamic range (background to 10 Mcps), and do not contain toxic or regulated materials, but the glass also scintillates in response to gamma radiation, which is problematic since it can cause unacceptably high false neutron alarms. The proposed material to be developed will have significantly lower gamma sensitivity as compared to the bulk glass or optical fibers and will lead to a transformational impact on the performance that can be achieved as compared to existing neutron detection systems.
The broader impact/commercial potential of this project includes filling a market need that is vitally important for the security of vulnerable nuclear weapons and materials, and for the prevention of illicit trafficking of these materials. The effectiveness of detection systems at high-risk border crossings, airports and seaports, as well as at nuclear weapons and components storage locations and research reactors, will be improved. Since neutrons are not emitted by most radionuclides used for medical or industrial purposes, the detection of neutrons is usually an unambiguous indicator of the presence of special nuclear materials (SNMs). Because the vast majority of neutron detection systems in existence today rely on 3He proportional counters and there is currently a global shortage of 3He, a suitable alternative neutron detection technology is urgently needed.
The detection of neutrons is vitally important for the security of vulnerable nuclear weapons and materials, and for the prevention of illicit trafficking of these materials, as well as a variety of commercial applications. Because the vast majority of neutron detection systems in existence today rely on 3He proportional counters and there is currently a global shortage of 3He, a suitable alternative neutron detection technology is urgently needed. Currently Ce3+ activated 6Li glass scintillator technology is used to produce neutron detectors that are extremely sensitive, rugged, flexible in design geometry, have a large dynamic range, and do not contain toxic or regulated materials, but the glass also scintillates in response to gamma radiation, which is problematic since it can cause unacceptably high false neutron alarms. In Phase I research Nucsafe developed a novel composite material containing Ce3+/6Li glass in the form of microspheres with strategically controlled dimensions that had significantly lower gamma sensitivity as compared to the bulk glass or optical fiber-based detectors. Small scintillators made of the composite material were fabricated for proof-of-concept testing. The predicted material and device performance goals were all met; in fact, the performance of test devices has exceeded our expectations. The long-term goal is to further develop this technology so that detectors with improved performance and lower cost can replace the fiber detectors in, e.g. backpacks, vehicle-mounted detectors, and pedestrian and vehicle portal systems.
