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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.
M. E. Dunn
Nuclear Science and Engineering | Volume 142 | Number 1 | September 2002 | Pages 48-56
Technical Note | doi.org/10.13182/NSE02-A2286
Articles are hosted by Taylor and Francis Online.
The Reich-Moore (RM) formulation is used extensively in many isotope/nuclide evaluations to represent neutron cross-section data for the resolved-resonance region. The RM equations require the evaluation of complex matrices (i.e., matrices with complex quantities) that are a function of the resonance energy and corresponding resonance parameters. Although the RM equations are documented in the open literature, computational pitfalls may be encountered with the implementation of the RM equations in a cross-section processing code. Based on experience, numerical instabilities in the form of nonphysical oscillations can occur in the calculated absorption, capture, or elastic scattering cross sections. To illustrate possible numerical instabilities, the conventional RM equations are presented, and the conditions that lead to numerical problems in the cross-section calculations are identified and demonstrated for 28Si and 60Ni. In an effort to circumvent the computational problems, detailed or revised RM expressions have been developed to efficiently and accurately calculate cross sections for neutron-induced reactions in the resolved-resonance region. The revised equations can be used to avoid numerical problems associated with the implementation of the RM formulation in a cross-section processing code. The revised Reich-Moore equations are also used to demonstrate the improved cross-section results (i.e., without numerical instabilities) for 28Si and 60Ni.