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August 24–27, 2026
Dallas, TX|Hilton Anatole
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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.
N. N. Kaushal, B. K. Malaviya, M. Becker, E.T. Burns, E. R. Gaerttner
Nuclear Science and Engineering | Volume 49 | Number 3 | November 1972 | Pages 330-348
Technical Paper | doi.org/10.13182/NSE72-A22546
Articles are hosted by Taylor and Francis Online.
Fast neutron spectra in a cuboidal assembly of uranium depleted in the 235U isotope have been measured for the purpose of providing integral checks on cross-section data pertinent to fast reactor development. Spectral measurements have been made at three different radial distances and several different angles, and cover an energy range from 10 keV to 10 MeV. The experimental spectra are compared with Sn transport calculations involving ENDF/B-I, ENDF/B-II, KEDAK (from Karlsruhe) files, and a multigroup set from Argonne National Laboratory and conclusions are drawn as to the adequacy of these data for predicting measured spectra. Extensive use is made of the continuous slowing down theory to pinpoint specific areas of uncertainty in the cross-section data. From a comparison of the experimental spectra with the calculations, it is concluded that the neutron capture cross-section data in the 238U ENDF/B files should be lowered by about 10% in the range 10 to 40 keV. Additionally, the slowing down effectiveness of inelastic scattering in the range 40 to 500 keV should be lowered by about 25%. Discrepancies among various data files are also observed in the inelastic slowing down effectiveness in the range 1 to 2 MeV.
