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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.
R. L. Walsh
Nuclear Science and Engineering | Volume 102 | Number 2 | June 1989 | Pages 119-133
Technical Paper | doi.org/10.13182/NSE89-A23637
Articles are hosted by Taylor and Francis Online.
Calculations of fission neutron spectra and fission spectrum integrals for six fissioning systems are reported. The systems studied are thermal-neutron-induced fission of 233U, 235U, and 239Pu; 2-MeV neutron fission of 232Th and 238U; and spontaneous fission of 252Cf The Madland-Nix formalism is used, but is extended to take account of the spin of the fission fragment. Also, more recent values for the average energy release in fission are used. The results of the fission neutron spectrum calculations are given in tabular and graphical form for applied purposes and are compared with experimental data. Similar deviations from a Maxwellian spectrum are seen for each system. The effect on the fission neutron spectra of 233U, 235U, and 239Pu from inclusion of alternative values for the average total fragment kinetic energy is shown.