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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.
G. R. Dalton, R. K. Osborn
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 481-492
Technical Paper | doi.org/10.13182/NSE64-A20991
Articles are hosted by Taylor and Francis Online.
An integral form of the one-speed neutron-transport equation is applied to the case of a neutron-detecting foil placed in a homogeneous medium with an initially non-isotropic neutron population. A series of numerical calculations have been carried out to investigate the effect on the self-shielding flux-depression factor of anisotropy in the initial undisturbed flux. The case of a square foil of gold placed in a light-water medium is investigated. It is found that the existence of anisotropy in the initial flux leaves the flux correction factor essentially unchanged. However, the presence of anisotropy implies spatial non-uniformity of the scalar flux. Thus, movement of the center of mass of a foil in a flux which has a gradient, or rotation of a foil in a flux which has a second derivative can alter the undisturbed flux and the disturbed flux to which a foil is exposed, though the flux correction factor remains unchanged.