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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. L. Williams, M. Asgari
Nuclear Science and Engineering | Volume 121 | Number 2 | October 1995 | Pages 173-201
Technical Paper | doi.org/10.13182/NSE95-1
Articles are hosted by Taylor and Francis Online.
A procedure is presented to obtain a continuous-energy representation of the neutron spectrum using one-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. A new method called a submoment expansion is developed to accurately calculate the Legendre moments of the elastic scatter source for the PW transport calculation, and the coupling between the MG and PW calculations is discussed in detail. The continuous-energy flux spectra can be utilized as problem-dependent weighting functions to process self-shielded MG cross sections for reactor physics and/or criticality safety analysis. This calculational method has been implemented in a new PW transport code called CENTRM that can be executed as a module in the AMPX and SCALE computer code packages. An example application using ENDF/B-VI cross-section data to analyze critical benchmarks is presented.