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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.
P. Kafalas, M. Levenson, C. M. Stevens
Nuclear Science and Engineering | Volume 2 | Number 5 | September 1957 | Pages 657-663
Technical Paper | doi.org/10.13182/NSE57-A25432
Articles are hosted by Taylor and Francis Online.
The variation of alpha, the ratio σc/σf, has been determined for U235 and Pu239 as a function of position in EBR. Samples of U235 and Pu239 were exposed in the core, inner blanket, and outer blanket; the samples were analyzed radiochemically to determine the fraction fissioned and mass spectrometrically to determine the fraction which had undergone the capture process. The vertical and horizontal patterns of capture and fission probability have been determined. The variation of η in the reactor has been plotted, assuming that remains constant.
