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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.
Richard E. Faw
Nuclear Science and Engineering | Volume 29 | Number 2 | August 1967 | Pages 210-217
Technical Paper | doi.org/10.13182/NSE67-A18529
Articles are hosted by Taylor and Francis Online.
Energy spectra have been computed for protons, alpha particles, and their secondary electrons slowing down in water irradiated by 14.6-MeV neutrons. Spectra for protons and alpha particles were based on continuous slowing down theory. Anisotropy of the proton-recoil reaction and elastic nuclear collisions of charged particles were found to have negligible influence on energy spectra and the energy-loss distribution. Partitioning of the neutron first-collision dose rate among the three particles was found to be very sensitive to the cutoff energy for production of secondary electrons. An analysis based on treatment of a collisional energy loss of less than 200 eV as localized energy dissipation along a particle track showed that localized electronic energy loss is distributed among protons, alpha particles, and their secondary electrons in the respective fractions 0.530, 0.112, and 0.358.