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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. W. Weston, J. H. Todd
Nuclear Science and Engineering | Volume 84 | Number 3 | July 1983 | Pages 248-259
Technical Paper | doi.org/10.13182/NSE83-A17793
Articles are hosted by Taylor and Francis Online.
The ratios of the neutron fission cross sections σf(240Pu)/σf(239Pu), σf(240Pu)/σf(235U), and σf(239Pu)/σf(235U) have been measured simultaneously with a multiplate ionization fission chamber using the Oak Ridge Electron Linear Accelerator as a neutron source over the neutron energy range from 5 keV to 20 MeV. The 240Pu ratio data are in overall agreement with ENDF/B-V with exceptions in relatively narrow neutron energy regions. Below 150 keV and from 10 to 20 MeV, the present 239Pu/235U fission ratios indicate significant discrepancies when compared to ENDF/B-V. These ratios are important for thermal and fast reactor applications.
