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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.
C. W. Maynard
Nuclear Science and Engineering | Volume 10 | Number 2 | June 1961 | Pages 97-101
Technical Paper | doi.org/10.13182/NSE61-A25945
Articles are hosted by Taylor and Francis Online.
In solving two-dimensional one-energy transport problems, it is often necessary to utilize Monte Carlo calculations in situations where this technique converges very slowly. In problems with regionwise constant sources where the required result is the flux at a point or an integral of the flux over a region or surface, the reciprocity theorem can be used to determine an auxiliary problem which yields the same information while in many cases improving the statistics appreciably. The relations required in choosing the auxiliary problem are derived. The required integrals and statistical errors are stated in terms of the results for the auxiliary problem. Examples are given to illustrate the application of these ideas to a flux peaking situation and to the absorption in a small region. The extension of this procedure to energy-dependent cases is discussed briefly.