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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The progress so far: An update on the Reactor Pilot Program
It has been about three months since the Department of Energy named 10 companies for its new Reactor Pilot Program, which maps out how the DOE would meet the goal announced by executive order in May of having three reactors achieve criticality by July 4, 2026.
M. M. R. Williams
Nuclear Science and Engineering | Volume 199 | Number 7 | July 2025 | Pages 1107-1161
Research Article | doi.org/10.1080/00295639.2024.2444147
Articles are hosted by Taylor and Francis Online.
An extension of the work of Pázsit, Dykin, and Darby on multiplet evaluation has been made using a different method of solution and with the addition of an external reflecting material. The method of solution uses the scalar form of the transport equation to calculate the singlet, doublet, and triplet moments, and in the case when the source configuration requires it, the angular distribution can be obtained in terms of the scalar quantities by direct quadrature. The main contribution of this work is to demonstrate that the scalar approach is convenient, and if energy and anisotropic scattering are required, it is reasonably easy to make use of existing computer codes for solutions of the neutron transport equation. Also, it is shown that the addition of an external reflecting region can have a significant effect on the three multiplicity moments. Some numerical results are given to enable direct comparison to be made with other methods of solution.