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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.
G. R. Dalton
Nuclear Science and Engineering | Volume 20 | Number 2 | October 1964 | Pages 131-137
Technical Paper | doi.org/10.13182/NSE64-A28926
Articles are hosted by Taylor and Francis Online.
A method of doing PN calculations which is particularly useful for classroom use is presented. The method is basically a systematic numerical implementation of the analytic method of characteristic solutions. The extensive tabulations of characteristic roots are used as guide lines for the solution of the characteristic (N + 1) order polynomial equation. Then the tables of coupling coefficients are used to guide the evaluation of the coupling or recursion relations. The systematics of matrix algebra is next used to set up the linear equations resulting from the boundary conditions and to reconstruct the angular moments and the angular fluxes. The use of these tabulated guide lines and matrix operations to provide the single and double summations reduces the problem to a very managable level. A sample P3 problem treated in this manner is presented.