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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.
William G. Pettus
Nuclear Science and Engineering | Volume 11 | Number 2 | October 1961 | Pages 129-132
Technical Paper | doi.org/10.13182/NSE61-A28057
Articles are hosted by Taylor and Francis Online.
The age of U235 fission neutrons to indium resonance energy has been measured in a number of lattices of Th-H2O and Th-Al-H2O and compared with theoretical calculations. As a check on the procedure similar measurements were made in pure water yielding a result of 27.0 ± 0.9 cm2. In addition, the ratio of the age of U233 fission neutrons to the age of U235 fission neutrons in water was found to be 0.948 ± 0.033.
