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2026 Annual Conference
May 31–June 3, 2026
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Seconds Matter: Rethinking Nuclear Facility Security for the Modern Threat Landscape
In today’s rapidly evolving threat environment, nuclear facilities must prioritize speed and precision in their security responses—because in critical moments, every second counts. An early warning system serves as a vital layer of defense, enabling real-time detection of potential intrusions or anomalies before they escalate into full-blown incidents. By providing immediate alerts and actionable intelligence, these systems empower security personnel to respond decisively, minimizing risk to infrastructure, personnel, and the public. The ability to anticipate and intercept threats at the earliest possible stage not only enhances operational resilience but also reinforces public trust in the safety of nuclear operations. Investing in such proactive technologies is no longer optional—it’s essential for modern nuclear security.
Baiba V. Harrington, Geoffrey Constantine
Nuclear Technology | Volume 109 | Number 1 | January 1995 | Pages 11-20
Technical Paper | Fission Reactor | doi.org/10.13182/NT95-A35065
Articles are hosted by Taylor and Francis Online.
A calculational model of the entire core of the DIDO class reactor HIFAR has been used to analyze epithermal neutron beam experiments. In the experiments, an off-center fuel element was replaced by a dummy fuel element voided by a dry liner in which an aluminium spectrum shifter was suspended at core center to extract the beam. Various combinations of the filter materials aluminum, iron, sulfur, titanium, and cadmium were inserted near the top of the dry liner, and liquid argon was placed in a cryostat above the dummy element. Reaction rates were measured in a fission chamber, sandwiched between various thicknesses of polyethylene, in order to assess the accuracy of the calculational model for different regions of the neutron energy spectrum of the beam. The neutron source distribution of the HIFAR core was obtained from a three-dimensional diffusion calculation, with burnup-dependent fuel compositions and fission products included, using the AUS modular code scheme. Argon cross sections were generated from ENDL-84 data and resonance parameters taken from Neutron Cross Sections (1984). A whole-core MCNP source calculation was used to analyze the experiments giving good agreement between measured and calculated reaction rates. This whole-core model of HIFAR may be applied with confidence to predict the performance of filtered beams for boron neutron capture therapy and also to other HIFAR calculations.
