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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.
Harry Alter
Nuclear Science and Engineering | Volume 23 | Number 3 | November 1965 | Pages 264-271
Technical Paper | doi.org/10.13182/NSE65-A19560
Articles are hosted by Taylor and Francis Online.
The Monte Carlo code TYCHE-III has been used to calculate with a high degree of convergence the second, fourth, and sixth spatial moments of the slowing-down density distribution at the indium resonance energy, for neutrons originating from a fission source at a point in infinitely extended water and zirconium-water moderators. The effects of both inelastic scattering and anisotropy of elastic scattering in oxygen and zirconium have been included. For water, the calculations were performed using several widely available sets of data on oxygen cross sections and angular distributions. The effects on the neutron age and higher spatial moments of several fission spectra are also reported. These calculations have been compared with the moments of experimentally measured distributions of neutron flux at the indium resonance energy, after applying a suitable correction to the computed slowing-down moments. The agreement between the calculated and measured values of the neutron ages and higher moments is seen to be satisfactory.