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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.
G. T. Chapman, W. R. Burrus
Nuclear Science and Engineering | Volume 34 | Number 2 | November 1968 | Pages 169-180
Technical Paper | doi.org/10.13182/NSE68-A19542
Articles are hosted by Taylor and Francis Online.
Measurements of the pulse-height distribution of gamma rays observed as a function of position and angle in the water shield of the Bulk Shielding Reactor II, a water-moderated and water-cooled pool-type reactor with stainless steel clad fuel plates, have been transformed to gamma-ray energy flux spectra by a computer program which removed the effects of the spectrometer's nonunique pulse-height response and accounted for the energy variation of the spectrometer's efficiency. The results show that the photons above 5 MeV originate primarily from thermal-neutron capture in the components of the stainless steel. Gamma rays due to the 57Fe component were identified as those known to be at 5.91, 6.02, and 7.6 MeV. Others were due to 58Fe at 10.16 MeV, to 54Cr at 8.88 and 9.72 MeV, and to 59Ni at 8.53 and 8.99 MeV. Below 5 MeV the spectra consist of a strong contribution at 2.2 MeV from thermal-neutron capture in the hydrogen of the pool water, combined with a continuum presumably composed of prompt and delayed gamma rays following fission, lower energy components in the capture spectra from the stainless steel, scattering in the reactor or shield, and other lesser sources.