skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Detection of Special Nuclear Material in Cargo using Continuous Neutron Interrogation and Tension Metastable Fluid Detectors

Journal Article · · Transactions of the American Nuclear Society
OSTI ID:23042604
 [1];  [2];  [1]
  1. Metastable Fluid Research Laboratory, Purdue University School of Nuclear Engineering, Lafayette, IN, 47906 (United States)
  2. Sagamore Adams Laboratory, LLC., 190 South LaSalle Street, Chicago, IL, 60603 (United States)

This paper presents results using a novel technique for detecting special nuclear materials (SNMs) based on interrogation with a continuous beam of 2.45 MeV neutrons coupled with high intrinsic efficiency tensioned metastable fluid detectors (TMFDs) operated in threshold rejection mode. While passive interrogation may be utilized for detecting SNMs such as {sup 239}Pu from their strong spontaneous fission neutron signatures, this is not so for highly-enriched uranium (HEU), the timely detection of which has been identified as a grand challenge by the U.S. Domestic Nuclear Detection Office (DNDO). Active (neutron and/or photon based) interrogation represents the only viable means for detecting HEU either shielded or unshielded within cargo containers. Active interrogation by neutrons or photons leads to unequivocal induced fission based signatures in terms of neutron energy and multiplicity. The main challenge under such circumstances pertains to being able to discern the relatively weak emission signatures from the intense interrogation pulses of neutrons and/or photons. Purdue University together with Sagamore Adams Laboratories, LLC (SAL) has been developing the TMFD sensor system that promises to provide high neutron detection efficiency for fast and thermal neutrons while remaining gamma-beta blind. As described in these references, the TMFD sensor system works on the principle of transient cavitation detection events (CDEs) caused by ionizing particles such as neutrons, alphas and fission fragments in fluids that have been placed in various states of tensioned (sub-zero) pressure states of fluid metastability. Such CDEs result in recordable signatures - both electronically as for conventional detectors, but also in the form of audio-visual signals. One key advantage that the TMFD holds over conventional neutron detectors is that it has proven gamma-beta 'blindness' and indeed, confirmed to possess GARRn = 1.0 to γ photons (tested in up to 10{sup 11} γ/s field from a 3 Ci {sup 137}Cs source). Such an enablement allows for detection without saturation from background, interrogating and fission created γ photons. Another key attribute is up to 60 % intrinsic fission spectrum neutron detection efficiency which, furthermore, is amenable to tailoring for threshold based rejection. That is, to be able to detect neutrons at or above a desired energy with good efficiency, while remaining relatively blind to neutrons below the chosen threshold. This research is the subject of our ongoing DNDO project at Purdue University, the results of which form the basis of this paper. (authors)

OSTI ID:
23042604
Journal Information:
Transactions of the American Nuclear Society, Vol. 115; Conference: 2016 ANS Winter Meeting and Nuclear Technology Expo, Las Vegas, NV (United States), 6-10 Nov 2016; Other Information: Country of input: France; 8 refs.; available from American Nuclear Society - ANS, 555 North Kensington Avenue, La Grange Park, IL 60526 (US); ISSN 0003-018X
Country of Publication:
United States
Language:
English