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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. Reed Johnson, Daniel H. Risher, James E. Rogers, William L. Thompson
Nuclear Science and Engineering | Volume 43 | Number 1 | January 1971 | Pages 32-41
Technical Paper | doi.org/10.13182/NSE71-A21243
Articles are hosted by Taylor and Francis Online.
Well-collimated beams of thermal-neutron-capture gamma rays from titanium and nickel, having average energies of about 6 and 8 MeV, respectively, were used to measure narrow-beam and total gamma-ray dose attenuation. Slab shields of lead, iron, and concrete were investigated for normal and oblique beam incidence. Total dose measurements were made by traversing an exposure-responsive detector through a plane behind and parallel to the shield. Monte Carlo and moments-method calculations were used to compare analytical and experimental total dose results. Good agreement was found for iron and concrete shields, but experimental results for the lead shield were higher than those predicted by the moments method by a factor of ∼1.2 for 6 MeV and ∼1.5 for 8 MeV. The reason for this disagreement is believed to be primarily bremsstrah-lung produced by energetic secondary electrons slowing down in lead.