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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
Robert E. Rothe, D. C. Hunt
Nuclear Science and Engineering | Volume 54 | Number 3 | July 1974 | Pages 360-366
Technical Note | doi.org/10.13182/NSE74-A23427
Articles are hosted by Taylor and Francis Online.
Thirteen previously unpublished critical measurements on enriched (93.16 wt% 235U) uranium metal spheres, which are radially but not axially centered in cylinders of enriched (93.16 wt% 235U) uranium solution, are presented and compared with the results of Monte Carlo calculations. The average reproduction factor calculated for experimentally critical systems was k = 0.989, and this bias showed no systematic variation with the amount the sphere was displaced from center. The sphere size was increased, keeping other parameters constant, until criticality was calculated, at which point the average sphere radius and mass were 2.8 and 8.8%, respectively, greater than the experimental cases. For a given solution cylinder, the minimum critical metal sphere mass occurs when the sphere is centered in the solution. The increase in this critical mass with position along the cylinder axis is also presented parametric in two tank diameters and five solution concentrations. For like asymmetries and at the same concentration, a greater change in the critical sphere mass with position is seen for tanks of large diameter than for smaller tanks. If the tank diameter is fixed, the greater change occurs for solution of high uranium concentration.