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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, P. W. McKenty, K. L. Peddicord
Nuclear Science and Engineering | Volume 64 | Number 2 | October 1977 | Pages 317-331
Technical Paper | doi.org/10.13182/NSE77-A27373
Articles are hosted by Taylor and Francis Online.
The multiple collision technique as applied to the monoenergetic time-dependent neutron transport equation for pulsed plane source emission in an infinite medium is used to obtain the flux due to a pulsed point source in the same medium. This result is then integrated to determine the flux due to the corresponding pulsed line source problem. The semi-infinite albedo problem is also shown to be solvable using the multiple collision approach. A generalization to include delayed neutrons follows directly from the multiple collision treatment, as does an equivalence between a monoenergetic time-dependent problem and a particular stationary slowing down problem in infinite geometry. Results are tabulated and comparisons are made to provide benchmark solutions to the fundamental time-dependent transport problems considered and thus bridge the gap between theory and practice.