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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.
C. Lajeunesse, W. E. Moore, M. L. Yeater
Nuclear Science and Engineering | Volume 47 | Number 3 | March 1972 | Pages 349-364
Technical Paper | doi.org/10.13182/NSE72-A22420
Articles are hosted by Taylor and Francis Online.
The double-differential scattering cross section of polycrystalline natural uranium carbide (UC) has been measured for incident energies of 0.092, 0.135, and 0.159 eV. Inelastic scattering peaks corresponding to excitation energies of 0.013 and 0.045 eV were observed and are shown to belong to acoustic and optical modes of the UC lattice. A model has been developed using a normal mode analysis based on the Born and Von Kármán approximation, including noncentral forces and considering up to third-nearest neighbors. A theoretical scattering law has been derived based on this analysis. Resolution and multiple scattering effects have been calculated using a new Monte Carlo approach. After the application of these corrections, the double differential cross sections derived from the theoretical scattering law agree with the measurements. The variation of the specific heat with temperature is accurately predicted by the model. The total cross section was also measured for the energy range 0.006 to 3.5 eV. The Bragg peaks due to coherent scattering were resolved up to 0.05 eV. The total cross section calculated from our noncentral force model compares well with this measurement.