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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.
S. N. Cramer
Nuclear Science and Engineering | Volume 139 | Number 2 | October 2001 | Pages 186-208
Technical Paper | doi.org/10.13182/NSE01-A2231
Articles are hosted by Taylor and Francis Online.
Several one-energy group, discrete-direction radiation transport systems having analytic flux solutions are presented as an aid in Monte Carlo benchmark analysis techniques independent of realistic geometry and cross-section data requirements. Exact comparison of analytic and Monte Carlo results to several significant digits is possible for up to 26 directions in one, two, and three dimensions. A continuous direction model has also been formulated from an infinite limit of the discrete-direction model. Complete analytic flux solutions are possible through the imposition of boundary sources dictated by assumed exponential solutions of the transport equation. Extensions to two energy groups, two cross-section media, secondary particle production, time dependence, and continuous slowing down are examined. A website is provided from which codes and sample output files for the analytic and Monte Carlo models can be downloaded.