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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.
C. K. Paulson, E. J. Hennelly
Nuclear Science and Engineering | Volume 55 | Number 1 | September 1974 | Pages 24-27
Technical Paper | doi.org/10.13182/NSE74-A23962
Articles are hosted by Taylor and Francis Online.
High-energy neutron cross sections for 237Np are needed to calculate unwanted 236Pu contaminant in 238Pu product made for heat source applications in space and medical projects. Recent improved determination of 236Pu formation by 237Np(n, 2n) reactions completes the information needed to calculate 236Pu/238Pu ratios over a wide range of 237Np irradiation environments, from D2O reflectors to pressurized-water-reactor fuel. The 237Np(n, 2n) 236&Np cross section is 63 ± 6 mb, averaged over the 235U fission spectrum >6.8 MeV; this result is consistent with the cross section calculated by Pearlstein.
