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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.
J. C. Young, J. M. Neill, P. d’Oultremont, E.L. Slaggie, C. A. Preskitt
Nuclear Science and Engineering | Volume 48 | Number 1 | May 1972 | Pages 45-50
Technical Paper | doi.org/10.13182/NSE72-A22455
Articles are hosted by Taylor and Francis Online.
Neutron spectra have been measured between 50 eV and 8 MeV by the time-of-flight method in the core of a fast subcritical assembly, designated STSF-1A. This core is loaded with plate-type elements consisting of BeO, enriched uranium, and depleted uranium. The measurements were made at the surface of the central BeO plate. Reduction of the data and comparison to transport calculations followed the procedures used for the STSF-2 and STSF-2A assemblies, which were described in detail in a previous paper. The STSF-1A is similar in most significant details to ZPR-3 Assembly 57, built at ANL/Idaho, in which the spectrum was measured with a proton recoil detector, and this similarity permitted a comparison of the time-of-flight and proton-recoil techniques. The two methods have been found to be generally in satisfactory agreement.