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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.
Stanley C. Fultz
Nuclear Science and Engineering | Volume 6 | Number 4 | October 1959 | Pages 313-319
Technical Paper | doi.org/10.13182/NSE59-A28850
Articles are hosted by Taylor and Francis Online.
A two-group analysis has been applied to the transient behavior of the thermal flux in a subcritical assembly which has been given a short burst of fast neutrons. This analysis has been applied to graphite-U235 reactors having moderator-to-fuel (C/U) atomic ratios of 600, 1200, 2340, and 9550. The results are shown to be in agreement with measurements of the decay of thermal neutrons when short pulses of fast neutrons are incident on assemblies having these C/U ratios.
