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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.
Adimir dos Santos, Ricardo Diniz
Nuclear Science and Engineering | Volume 178 | Number 4 | December 2014 | Pages 459-478
Technical Paper | doi.org/10.13182/NSE14-10
Articles are hosted by Taylor and Francis Online.
The evaluation of the experiments of the effective delayed neutron parameters and reactivity performed in the IPEN/MB-01 research reactor facility has been successfully accomplished. The evaluated data are of very good quality and fulfill the requirements of a benchmark. The recently released MCNP6 together with the ENDF/B-VII.1, JENDL-4.0, JEFF-3.1.1, ENDF/B-VII.0, and JENDL-3.3 nuclear data libraries has been employed to calculate the effective delayed neutron parameters adopting the benchmark model of the IPEN/MB-01 reactor available in the International Handbook of Reactor Physics Benchmark Experiments. The analysis reveals that all these nuclear data libraries produced satisfactory results for βeff, βeff/Λ, and Λ. The same cannot be said for determining the reactivity using the Inhour equation. It was shown that there is a clear tendency to increase the deviation with the absolute value of the reactivity for negative periods. Only JENDL-3.3 and JEFF-3.1.1 produced results that are inside the 3σ range of the benchmark value uncertainty. Specifically for the case of ENDF/B-VII.1, a good part of this discrepancy is due to the decay constant of the first group of delayed neutrons, which is overestimated according to the experimental value measured in the IPEN/MB-01 reactor.