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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.
W. Maurice Pritchard, Tino Ahrens
Nuclear Science and Engineering | Volume 22 | Number 2 | June 1965 | Pages 248-252
Technical Paper | doi.org/10.13182/NSE65-A20243
Articles are hosted by Taylor and Francis Online.
Expressions have been derived for computing the effects of anisotropic neutron scattering in the center-of-mass system on the average cosine and the average cosine squared of the scattering angle in the laboratory system, the average logarithmic energy decrement per collision, the average square of the logarithmic energy decrement per collision if the angular distribution of the neutron scattering cross section in the center-of-mass system in known. In a Legendre polynomial representation, the effect of scattering anisotropy is to require additive correction terms to the usual isotropic scattering approximations for these parameters. The magnitudes of the correction terms depend on the mass of the scattering atom and the degree of anisotropy exhibited by the scattering cross section in the center-of-mass system.