Abstract: Active special nuclear material (SNM) photoneutron interrogation research with Tensioned Metastable Fluid Detector (TMFD) sensor technology demonstrated the TMFD technology to readily and conclusively detect the presence of SNM while remaining insensitive to the intense 36,000 R h ^-1 9 MeV endpoint X-ray background. Results for the centrifugally and acoustically tensioned metastable fluid detectors show how SNM (uranium) fission neutron energy detection thresholds can be used to detect SNMs under intense radiation conditions wherein conventional state-of-art detectors get saturated.

Keywords: Active Photon Interrogation, Special Nuclear Material, Linear Accelerator, Tension Metastable Fluid Detectors.

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