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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.
P. Barbucci, F. Di Pasquantonio
Nuclear Science and Engineering | Volume 63 | Number 2 | June 1977 | Pages 179-187
Technical Paper | doi.org/10.13182/NSE77-A27021
Articles are hosted by Taylor and Francis Online.
The use of supplementary exponential equations to solve the transport equation by means of the discrete ordinate method has been studied. It is shown that the set of final equations so obtained can be easily and quickly solved on the computer using the same iterative procedure employed in standard SN codes. The new method is implemented on ANISN and DOT-III codes. This work refers only to the one-dimensional case. Extensive numerical experiments for neutrons and gamma rays showed that the exponential scheme increases the convergence rate of the iterative procedure and always overestimates the “reference solution” by very small amounts for the finest mesh size and by reasonable amounts for the largest mesh size. For its own structure, the exponential method always gives positive angular fluxes without any adjustment techniques provided the source is non-negative.