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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.
Roger B. DeBar
Nuclear Science and Engineering | Volume 30 | Number 2 | November 1967 | Pages 159-165
Technical Paper | doi.org/10.13182/NSE67-A17326
Articles are hosted by Taylor and Francis Online.
The most general linear truncation relation for the spherical harmonic representation of the transport equation in three dimensions is shown in any order to be a partial differential equation. This equation is uniquely determined up to two independent scalar parameters in the time-dependent case and one scalar parameter in the time-independent case. In the time-dependent situation, one of the parameters may be related to the other parameter, which is pertinent to the time-independent limit, in such a way as to give correct retardation in all orders.
