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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.
Kiyoshi Takeuchi, Shun-ichi Tanaka
Nuclear Science and Engineering | Volume 90 | Number 2 | June 1985 | Pages 158-164
Technical Paper | doi.org/10.13182/NSE85-A17673
Articles are hosted by Taylor and Francis Online.
Gamma-ray exposure buildup factors are calculated using a discrete ordinates direct integration code, PALLAS-PL, SP-Br, for water, concrete, iron, and lead for point isotropic sources. These data include the effects of secondary photon sources arising from Compton scattering, bremsstrahlung, and annihilation. Comparisons of these results without bremsstrahlung to values obtained earlier by moments calculations show reasonable agreement, except in some instances of deep penetration. The calculated buildup factors are tabulated for incident energies of 0.1 to 15 MeV (except for lead, where the lower energy is 0.4 MeV) and for penetration depths as great as 40 mfp.