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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.
Donald Bogart, Donald F. Shook, Daniel Fieno
Nuclear Science and Engineering | Volume 53 | Number 3 | March 1974 | Pages 285-303
Technical Paper | doi.org/10.13182/NSE74-A23354
Articles are hosted by Taylor and Francis Online.
Integral tests of evaluated ENDF/B high-energy cross sections have been made by comparing measured and calculated neutron leakage flux spectra from spheres of various materials. An Am-Be(α,n) source was used to provide fast neutrons at the center of the test spheres of beryllium, polyethylene, lead, niobium, molybdenum, tantalum, and tungsten. The absolute leakage flux spectra were measured in the energy range from 0.5 to 12 MeV using a calibrated NE-213 liquid scintillator neutron spectrometer. Absolute calculations of the spectra were made using Version-Ill ENDF/B cross sections and an Sn discrete-ordinates multigroup transport code., Generally excellent agreement was obtained for beryllium, polyethylene, lead, and molybdenum, and good agreement was observed for niobium although discrepancies were observed for some energy ranges. The poor comparative results obtained for tantalum and tungsten are attributed to unsatisfactory nonelastic cross sections. The experimental sphere leakage flux spectra are tabulated and serve as possible benchmarks for these elements against which reevaluated cross sections may be tested.