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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.
D. V. Gopinath, K. Santhanam, D. P. Burte
Nuclear Science and Engineering | Volume 52 | Number 4 | December 1973 | Pages 494-498
Technical Note | doi.org/10.13182/NSE73-A23320
Articles are hosted by Taylor and Francis Online.
The Anisotropic Source-Flux Iteration Technique (ASFIT) is a semianalytical method based on collision probabilities for energy-dependent radiation transport. In its original form, the coupled integral equations for space and energy-angle transmission were solved using discrete ordinate representation in space and energy and polynomial approximation in direction cosine for radiation flux and source terms. In this Note, the following modifications of ASFIT are presented: 1. discrete ordinate representation in direction cosine 2. sequential integration in space 3. exponential transformation in space 4. multiple energy structure for neutron transport. The Note discusses the rationale for these modifications, and their effect on the speed of computation, convergence, and capabilities of the code.