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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.
Zhaopeng Zhong, Thomas J. Downar, Yunlin Xu, Mark L. Williams, Mark D. DeHart
Nuclear Science and Engineering | Volume 154 | Number 2 | October 2006 | Pages 190-201
Technical Paper | doi.org/10.13182/NSE06-3
Articles are hosted by Taylor and Francis Online.
A method is presented to obtain a continuous-energy representation of the neutron spectrum using two-dimensional discrete ordinates calculations with a combination of multigroup (MG) and pointwise (PW) nuclear data. This provides the capability of determining the fine-structure energy distribution of the angular flux and flux moments within the resonance range as well as the smoother spectrum in the high- and thermal-energy ranges. The continuous-energy flux spectra can be utilized as problem-dependent weighting functions within the whole two-dimensional domain to process self-shielded MG cross sections for reactor physics and/or criticality safety analysis so that the two-dimensional heterogeneous effect in the resonance calculation can be fully considered. This calculational method has been implemented in a new PW transport code called GEMINEWTRN that may be executed as a module in the SCALE computer code system. Example applications using ENDF/B cross-section data are presented to study the two-dimensional heterogeneous effect in the resonance calculations.