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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. Budtz-Jørgensen, H.-H. Knitter
Nuclear Science and Engineering | Volume 79 | Number 4 | December 1981 | Pages 380-392
Technical Paper | doi.org/10.13182/NSE81-A21389
Articles are hosted by Taylor and Francis Online.
The neutron-induced fission cross section of 240Pu was measured in the neutron energy range from 10 keV to 10 MeV using the 7-MV Van de Graaff and the electron linear accelerator of the Central Bureau for Nuclear Measurements as pulsed neutron sources, which delivered monoenergetic and continuous neutron spectra, respectively. The neutron-induced fission events were detected with a parallel plate ionization chamber that provided a fast and narrow output signal allowing nanosecond timing, but where the time integral of the pulse contained, at the same time, the energy information of the ionizing particle. This detector permitted a high discrimination between alpha particles and fission fragments at an alpha emission rate of some 107 s−1. The fission cross-section data below 400 keV are especially remarkable since they were taken with an energy resolution almost one order of magnitude better than any other published data set. In this region, large structures in the fission cross section due to Class II states in the second well of the double-humped fission barrier were found. The spontaneous fission half-life of 240Pu was measured to be (1.15 ± 0.03)·1011 yr.