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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.
Juhani Pitkäranta, Pekka Silvennoinen
Nuclear Science and Engineering | Volume 52 | Number 4 | December 1973 | Pages 447-453
Technical Paper | doi.org/10.13182/NSE73-A23311
Articles are hosted by Taylor and Francis Online.
The finite element method is applied in multigroup formalism to the analysis of some fast and intermediate spherical critical systems. The approximation scheme is based on a self-adjoint variational principle associated with the formally self-adjoint form of the monoenergetic transport equation. A number of experimental critical assemblies are analyzed using unmodified and modified Hansen-Roach 16-group cross sections. Comparison of the results with those obtained by SN calculations indicates that high accuracy is obtained by low-order finite element techniques. Several optional strategies are proposed which may further accelerate the convergence of finite element solutions.