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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.
Alan Staub, E. M. Gelbard
Nuclear Science and Engineering | Volume 48 | Number 3 | July 1972 | Pages 359-361
Technical Note | doi.org/10.13182/NSE72-A22494
Articles are hosted by Taylor and Francis Online.
The application of the simplified spherical harmonics (SSH) method for neutron transport calculations of critical homogeneous spheres of aqueous solutions of uranium has been reexamined to estimate the error introduced by the use of the simplified P7 approximation. Recalculation of the critical spheres in the SSH-P7 approximation with modified Marshak boundary conditions showed that no substantial error was introduced in the earlier analysis.
