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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.
Keisuke Kobayashi and Tsuyoshi Misawa
Nuclear Science and Engineering | Volume 92 | Number 3 | March 1986 | Pages 407-420
Technical Paper | doi.org/10.13182/NSE86-A17529
Articles are hosted by Taylor and Francis Online.
It is shown that the semi-discrete ordinates equation can be used to create a computer program for a general order of PL approximations for solving the multigroup neutron transport equation in two-dimensional x-y geometry. Sample calculations for problems using up to a P7 approximation and up to four energy groups are given, and the results are compared with corresponding ones obtained by the discrete ordinates method. As the order of approximations increases, both results show good agreement, when the influence of the ray effect is not appreciable. The advantage of the present method is that the ray effect does not occur, which is the problem in the discrete ordinates method.