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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.
L. Green, J. J. Ullo
Nuclear Science and Engineering | Volume 67 | Number 2 | August 1978 | Pages 172-183
Technical Paper | doi.org/10.13182/NSE78-A15434
Articles are hosted by Taylor and Francis Online.
The spatial distribution of the total neutron density from a 252Cf source in pure water was measured to high statistical precision at distances ranging from 11 to 80 cm from the source. Assuming the adequacy of the ENDF/B-IV hydrogen cross sections and reasonable constraints on the fission spectrum mean energy, good agreement between experiment and a one-dimensional transport calculation was obtained for both ENDF/B-III and -IV oxygen cross sections, with Version III being slightly better. However, small residual differences remained that could not be removed by adjustment of the spectrum mean energy alone.