Beyond He-3 nuclear sensors — TMFDs for real-time SNM monitoring with directionality

Abstract

Due to He-3 shortages as well as other fundamental limitations of 60-y nuclear power technology being adapted for present-day sensor needs, transformational nuclear particle sensor system developments have sponsored by DARPA, DoE, DHS and NSF. These systems dispense with need for conventional He-3, liquid scintillation or solid-state devices. The novel systems detect a variety of radiation types via interactions with ordinary fluids such as water and acetone placed under metastable states of tensioned (yes, sub-zero or below-vacuum) liquid pressures at room temperature. Advancements have resulted which: enable directionality information in 30s to within 10 degrees of a weapons of mass destruction (WMD) neutron source at 25m (80ft); offer over 90% intrinsic efficiency; offer the ability to decipher multiplicity of neutron emission characteristic of spontaneous and induced fission from fissile isotopes; and, enable one to detect WMD-shielded neutrons in the 0.01 eV range, to unshielded neutrons in the 1–10 MeV range, coupled with the ability to detect alpha emitting special nuclear material (SNM) signatures to within 1–5 keV in energy resolution, and detection sensitivities to ultra-trace levels (i.e., to femto-grams per cc of SNMs such as Pu, and Am). The novel tension metastable fluid detector (TMFD) systems are robust, and are presently built in the laboratory with material costs in the ∼$50+ range — with inherent gamma blindness capability. A multi-physics design framework (including nuclear particle transport, acoustics, structural dynamics, fluid-heat transfer, and electro-magnetics), has also been developed, and validated. Comparison against He-3 technology is presented along with adaptation to variety of scenarios ranging from border crossings, to spent nuclear reprocessing plants to portals and moving platforms.