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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.
Wayne J. Mikols, J. Kenneth Shultis
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 738-743
Technical Note | doi.org/10.13182/NSE77-A15215
Articles are hosted by Taylor and Francis Online.
It is shown that for transport problems involving fine-energy-group structure or light element scattering, the elastic scattering transfer cross sections can be approximated by trapezoid-shaped distributions. In particular, for group structures of equal lethargy widths, the trapezoidal distribution reduces to a triangular shape. These approximate transfer cross sections are readily incorporated into a discrete ordinates code and often produce results superior to those obtained with conventional Legendre expansion techniques.