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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.
B. D. Ganapol, C. T. Kelley, G. C. Pomraning
Nuclear Science and Engineering | Volume 114 | Number 1 | May 1993 | Pages 12-19
Technical Paper | doi.org/10.13182/NSE93-A24010
Articles are hosted by Taylor and Francis Online.
It was recently demonstrated that in planar geometry, the classic PN equations are an asymptotic limit of the transport equation. A corresponding boundary layer analysis established the asymptotically consistent boundary conditions. These boundary conditions were evaluated variationally, and it was conjectured that these variational approximations are quite accurate for all values of N. Here, we evaluate these boundary conditions exactly (numerically) and show that the previous variational results are indeed accurate to a few percent. The exact results were computed using numerical methods previously developed for solving Chandrasekhar’s H equations.