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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.
M. Segev
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 229-235
Technical Note | doi.org/10.13182/NSE81-A21356
Articles are hosted by Taylor and Francis Online.
An equivalence principle is developed for an infinite array of annular rods. The center of a rod is a moderator characterized by the sticking probability γ1. Surrounding the center is an annular absorber characterized by the radii R1 < R2. The rods are uniformly distributed in an outer moderator characterized by the sticking probability γ2. The escape cross section for the lattice is The factor a is an adjustable Bell factor.
