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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.
H. I. Liou, R. E. Chrien, R. C. Block, K. Kobayashi
Nuclear Science and Engineering | Volume 67 | Number 3 | September 1978 | Pages 326-333
Technical Paper | doi.org/10.13182/NSE78-A27253
Articles are hosted by Taylor and Francis Online.
The size of the neutron cross-section minimum in 45Sc is important in the optimum design of filters for the production of 2-keV neutron beams. We have measured the scandium total cross section from 5 eV to 22 keV, an energy region in which high-resolution and high-precision cross-section data did not previously exist. The samples used are in metallic form having thicknesses ranging from 0.2 to 30.5 cm. We find that the cross section at the (2.05 ± 0.02)-keV minimum is (0.71 ± 0.03) b, in sharp contrast to the previously accepted value, 0.085 b. The size of the cross section indicates that an optimum scandium filter would be shorter than what is conventionally used. An R-function shape fit with constraints from the known thermal cross sections showed that J = 3 scattering dominates at thermal energy, in contradiction to a previous result obtained by polarization techniques. Our conclusion is supported by 45Sc(n, γ) spectra, and the transmission measurements using polarized neutrons and targets. Scandium level parameters were extracted for each observed resonance up to 22 keV. S-wave strength functions and average level spacings were also evaluated for both spin states.