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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.
J. K. Fletcher
Nuclear Science and Engineering | Volume 77 | Number 3 | March 1981 | Pages 367-372
Technical Note | doi.org/10.13182/NSE81-A19846
Articles are hosted by Taylor and Francis Online.
The source-free monoenergetic transport equation can be written as where for plane and for spherical geometries, respectively; Ω is the direction of motion with θ as its angle to the axis, An analytic expression for ψ(Z, cosθ) of the form is considered where Pn(cosθ) is the Legendre polynomial of order n; are combinations of exponential functions for the plane case and Bessel functions in the spherical formulation. A simple algorithm is developed that enables solutions to be found for any N using a small computer program.