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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.
M. P. Fricke, J. M. Neill
Nuclear Science and Engineering | Volume 50 | Number 4 | April 1973 | Pages 392-397
Technical Note | doi.org/10.13182/NSE73-A26576
Articles are hosted by Taylor and Francis Online.
The neutron spectrum and criticality of ZPR-3 Assembly 11 have been calculated using estimated cross sections for the mU(n, γn’) reaction. Inclusion of this reaction markedly improves agreement between the measured and calculated spectra, and it also decreases the calculated criticality by 0.62%. This change in criticality can be compensated for by lowering the 238U capture cross section from the ENDF/B-III values to those of a recent microscopic measurement. These and other ramifications of the (n,γn’) reaction in fast reactor assemblies are discussed.
