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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.
F. B. Simpson, J. W. Codding, Jr.
Nuclear Science and Engineering | Volume 28 | Number 1 | April 1967 | Pages 133-138
Technical Paper | doi.org/10.13182/NSE67-A18676
Articles are hosted by Taylor and Francis Online.
Transmission measurements on 233Pa have been taken with the Materials Testing Reactor (MTR) fast chopper. The total cross section has been calculated in the energy range from 0.01 to 10 000 eV. These measurements were made on 700 mg of chemically separated 233Pa in an oxide form. The protactinium was produced by irradiating 280 g of 232Th in the Engineering Test Reactor (ETR). The sample represented approximately 15 000 Ci of activity. The data were taken with a resolution of 0.08 to 2.0 μsec/m. The Breit-Wigner (B-W) resonance parameters have been obtained for the resonances below 18 eV. The average parameters give a value of 0.75 × 10 −4 for the s-wave neutron strength function . Weighting the level spacings inversely as 2J + 1 gives the average observed level spacings per spin state of 1.10 and 1.84 eV. A second-order polynomial least-squares fit to the data between 0.01 and 0.10 eV gives a 2200 m/sec total neutron cross section of 55 ± 3 b, superseding a value of 57 b given previously. The resonance-absorption integral for neutrons with energies above 0.4 eV was calculated to be 901 ± 45 b.