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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.
Gad Shani
Nuclear Science and Engineering | Volume 52 | Number 4 | December 1973 | Pages 439-446
Technical Paper | doi.org/10.13182/NSE73-A23310
Articles are hosted by Taylor and Francis Online.
When a propagating neutron wave reaches an interface between two media, a part of it is transmitted and a part is reflected. In the present work, neutron waves reflected from the core and from the reflector are compared. The following is concluded: Reflection exists in both cases. When the first medium in which the wave is propagating is a multiplying medium, it is much easier to detect the reflected wave than it is in the nonmultiplying diffusive medium. The reflected wave amplitude and phase depend much more on the properties of the first medium than on the properties of the reflecting medium. Neutron waves reflected back into the core are in phase with the propagating waves and hence reinforce them. Neutron waves reflected by the core are out of phase with the propagating waves and hence weaken them. Other characteristics of the amplitudes and phases of waves in both cases are compared.