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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.
F.H. Fröhner
Nuclear Science and Engineering | Volume 103 | Number 2 | October 1989 | Pages 119-128
Technical Paper | doi.org/10.13182/NSE89-A28501
Articles are hosted by Taylor and Francis Online.
The state of the JEF-2 evaluation of 238 U + n cross sections in the region of unresolved resonances (∼10 to 300 keV) is reported with special emphasis on recent progress in theory (rigorous expressions for resonance-averaged cross sections with arbitrary level overlap), which permits reliable model-aided evaluation and parameterization by simultaneous fits to total, capture, and inelastic scattering cross-section data. Formalized inclusion of information from resolved resonances via Bayes' theorem has helped to remove discrepancies between resolved and unresolved parameters and has improved resonance statistics. Comparison with the latest ENDF/B-VI (pointwise) evaluations of the capture and the total cross sections shows agreement within 1 to 3%.