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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.
L. L. Carter, N. J. McCormick
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 296-310
Technical Paper | doi.org/10.13182/NSE70-A19991
Articles are hosted by Taylor and Francis Online.
A scheme is devised which combines in a coupled manner the sampling from the transport equation and the adjoint transport equation to improve the sampling for a functional such as the space- and velocity-dependent neutron distribution due to a given source distribution. Specific use is made of sampling from the transport equation to construct a scheme for a near-optimal subsequent sampling from the adjoint equation, even when inelastic scattering is present. The energy-dependent reciprocity relation is utilized to relate the solution of the adjoint equation to that of the transport equation itself. This procedure may be expected to be advantageous when the phase-space volume contributing to the functional in the region of interest is smaller than that volume in the source region. Numerical results demonstrate that calculation times in two example problems can be significantly reduced with the coupled sampling approach.