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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. Pahor, H. A. Larson
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 420-432
Technical Paper | doi.org/10.13182/NSE72-A22510
Articles are hosted by Taylor and Francis Online.
The non-uniqueness of solutions of the nonlinear integral equations for the generalized Chandrasekhar′s function and H matrix for a homogeneous halfspace is discussed, and a new uniquely soluble equation for the H matrix is constructed. Then the complete solutions for the half-space albedo and Milne problems for thermal neutrons with the isotropic scattering degenerate kernel are derived. The solutions are expanded in terms of the infinite medium eigenfunctions and the expansion coefficients are determined from the corresponding emergent distributions, which have been discussed in an earlier paper and expressed in terms of the H matrix. In solving the albedo problem, the half-range completeness of the eigenfunctions is demonstrated and the corresponding halfrange closure relation is derived. At the end, numerical results for the heavy gas scattering model are presented.