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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.
G. de Saussure, L. C. Leal, R. B. Perez, N. M. Larson, M. S. Moore
Nuclear Science and Engineering | Volume 103 | Number 2 | October 1989 | Pages 109-118
Technical Paper | doi.org/10.13182/NSE89-A28500
Articles are hosted by Taylor and Francis Online.
A new evaluation of the “resolved resonance range” for the neutron cross sections of 235U is described. Up to 110 eV, the evaluation is based on an R-matrix analysis of several fission, capture, and transmission measurements. Levels above 110 eV are no longer resolved so that many resonances are missed; from 110 to 500 eV, most of the important resonances can be identified and analyzed so that the cross section and transmission data are well represented by the proposed parameters. From 500 to 2250 eV, fictitious parameters are provided that describe fairly well the results of thick sample transmission measurements and recent fission cross-section data. Such a parameterization is likely to yield a better approximation of resonance self-shielding than the current ENDF/B- V unresolved resonance treatment.