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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.
S. B. Gunst
Nuclear Science and Engineering | Volume 6 | Number 5 | November 1959 | Pages 376-378
Technical Paper | doi.org/10.13182/NSE59-A25674
Articles are hosted by Taylor and Francis Online.
In the calculation of irradiation-induced changes in reactivity in natural uranium, the direct formation of Pu239 upon neutron capture in U238 is frequently assumed. The attendant error in reactivity during irradiation is shown to be significant for an illustrative case even after high exposure. This suggests that the consequences should be examined when the direct formation of Pu239 is assumed.
