An entire family of neutron detection formats benefit from the novel approach of incorporating 10B and Gd into the base materials used for the electron multiplier. NOVA has developed a series of three derivatives of MCP technology which not only detect neutrons, but operate as electron multipliers. The initial development was the Microsphere Plate (MSP) as shown in the following figure. This approach was originally developed by El-Mul in Isreal. employs . NOVA further developed the incorporation of neutron absorbers and demonstrated the ability to image neutrons.
Advantages accruing to the MSP approach include much larger formats than that available with MCPs, reducing processing, and spatial resolution capability of some 250 µm. These materials, in all other ways, behave similarly to the MCP with the neutron reactant products creating secondary electrons at the sphere surfaces, and subsequently an electron pulse being developed within the interstices as shown below.
In a similar vein, NOVA also developed and demonstrated a revolutionary new MicroReticulated Plate (MRP) as shown below.
The MRP also operates like the MSP with the secondary electrons cascading through the structure finally reaching a pixilated or solid anode.
The third approach developed is the MicroFiber Plate (MFP) technology whereby small fibers are assembled into a working array as shown below. The MicroFiber Plate is capable of being inexpensively manufactured into large, arbitrarily shaped formats.
Each of these three approaches can provide large format arrays, simplified processing with reduced costs, medium spatial resolution for neutron imaging, and high detection efficiency. Importantly higher levels of boron and gadolinium can be attained in these systems because the constraints of MCP processing are relaxed, providing excellent options for next generation Special Nuclear Material detectors.
NOVA has been partially supported in these developments by the Department of Energy (DOE), the National Nuclear Security Administration (NNSA), and other agencies.
