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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.
P. A. Ombrellaro
Nuclear Science and Engineering | Volume 44 | Number 2 | May 1971 | Pages 204-220
Technical Paper | doi.org/10.13182/NSE71-A19669
Articles are hosted by Taylor and Francis Online.
Spectral synthesis methods, in which the space-energy flux is synthesized from known flux spectra, are applied to one-dimensional, fast reactor static problems. The methods include few-group synthesis models that employ either the same trial spectra in all regions of the reactor model or different trial spectra in different spatial regions. Numerical results demonstrate that the space-energy flux can be adequately represented by these few-group synthesis models; moreover, the spatially dependent spectra agree very well with similar, “exact” flux spectra calculated by direct multigroup methods. Region-integrated reaction rates calculated with the synthesized flux spectra are in good agreement with those calculated with the flux spectra derived from direct methods.