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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.
A. Leonard
Nuclear Science and Engineering | Volume 32 | Number 3 | June 1968 | Pages 342-349
Technical Paper | doi.org/10.13182/NSE68-A20216
Articles are hosted by Taylor and Francis Online.
A transport calculation of the lattice diffusion length, yielding the “gross” decay of the asymptotic flux in a lattice, is made using the method of K. M. Case. Refinements over the diffusion calculation are shown to be 1) slight adjustments in the slab widths due to boundary effects, and 2) the appearance of exact homogeneous diffusion lengths as calculated by transport theory. The extension to “asymptotic” time-dependent problems is also given. For the neutron-wave problem, the complex-valued diffusion length is derived as a function of frequency, and the relation between the time decay constant and the buckling is given for the pulsed-neutron problem. Limiting cases involving very wide slabs are discussed. Finally, some experiments are briefly described for which the analysis of this paper might be applicable.
