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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.
J. W. Boldeman, J. Fréhaut, R. L. Walsh
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 430-436
Technical Paper | doi.org/10.13182/NSE77-A27060
Articles are hosted by Taylor and Francis Online.
Corrections of the large liquid scintillator measurements by Boldeman et al. and Soleilhac et al. for the delayed gamma rays from fission have produced consistent values for the average number of prompt neutrons () produced in the fission of 235U. The absolute value of for thermal-neutron fission is 2.389 ± 0.009, and the energy dependence is approximately linear. The data do not support the existence of fine structure between 200 and 600 keV nor the broad step-like structural dependence found in recent evaluations. However, there is the suggestion of a slight flattening of the curve representing the data between 250 and 600 keV.