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2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
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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.
L. B. Engle, G. E. Hansen, H. C. Paxton
Nuclear Science and Engineering | Volume 8 | Number 6 | December 1960 | Pages 543-569
Technical Paper | doi.org/10.13182/NSE60-A25842
Articles are hosted by Taylor and Francis Online.
This report brings together an extensive accumulation of reactivity contribution data for the various critical assemblies at Pajarito. Corresponding values of effective absorption and transport cross sections are derived, and relationships between critical mass and volume fraction of diluents are obtained in terms of these cross sections. In some favorable cases, inelastic scattering contributions to the effective absorption cross sections are estimated.
