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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. Hardy, Jr., D. Klein, and R. Dannels
Nuclear Science and Engineering | Volume 26 | Number 4 | December 1966 | Pages 462-471
Technical Paper | doi.org/10.13182/NSE66-A18417
Articles are hosted by Taylor and Francis Online.
The intra-cell structure of the fast neutron flux has been measured in several TRX lattices with 238U (n, fission) and Al (n, α) detectors. The lattices were light-water-moderated, with cylindrical, 0.387-in.-diam fuel rods of slightly enriched uranium. The fuel rods were arranged in hexagonal arrays, with H2O:U volume ratios of 1.0, 2.35, 4.02, and 8.1. Measured activation shapes and integral fast advantage factors were compared with calculated results obtained with the MOCA2A Monte Carlo program. Agreement was very good. A one-group Monte Carlo calculation and a one-group collision-probability model were found to perform well in comparison with MOCA2A.
