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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.
Imre Pázsit
Nuclear Science and Engineering | Volume 112 | Number 4 | December 1992 | Pages 369-374
Technical Paper | doi.org/10.13182/NSE92-A23985
Articles are hosted by Taylor and Francis Online.
A new and simple derivation of the neutron transport equation is given. The approach is similar to that used in the Liouville equation and its applications to the Boltzmann equation in that it is formulated in terms of the one-particle or one-point density function, as opposed to the traditional reactor physics approach of counting neutrons in a volume of the phase-space. It makes use of the recognition that the expected number of particles in a phase cell dV is the same as the probability of finding one particle in dV. A novelty of the derivation here is that because of the linear Markovian property of the process, it is possible to derive a master (Chapman-Kolmogorov) equation for the one-particle density, that is, for the neutron density or neutron flux of the traditional transport equation. This way, the forward and the backward (adjoint) equations of neutron transport can be derived from a single master equation. The variance of the one-point distribution function is also derived, and an explicit solution is given.