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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.
Chris L. Castrianni, Marvin L. Adams
Nuclear Science and Engineering | Volume 128 | Number 3 | March 1998 | Pages 278-296
Technical Paper | doi.org/10.13182/NSE98-A1956
Articles are hosted by Taylor and Francis Online.
A strictly positive spatial discretization method for the linear transport equation is presented. This method, which is algebraically nonlinear, enforces particle conservation on subcells and approximates the spatial variation of the source in each subcell as an exponential. The method is described in slab geometry and analyzed in several limits of practical significance; numerical results are presented. An x-y-geometry version of the method is then presented, assuming a spatial grid of arbitrary polygons; numerical results are presented. A rapidly convergent method for accelerating the iterations on the scattering source is also presented and tested. The analyses and results demonstrate that the method is startlingly accurate, especially on shielding-type problems, even given coarse and/or distorted spatial meshes.