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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.
Toru Obara, Hiroshi Sekimoto
Nuclear Science and Engineering | Volume 130 | Number 3 | November 1998 | Pages 386-390
Technical Note | doi.org/10.13182/NSE98-A2014
Articles are hosted by Taylor and Francis Online.
The positive neutron temperature coefficient of reactivity of a dilute plutonium-water solution is discussed analytically and numerically. It is explained by the competition of the temperature sensitivity coefficients of microscopic thermal cross sections of fissile materials and absorbers. The use of 176Lu, 180Ta, or 167Er, which have absorption resonances at low energy, in the solution makes it possible for the neutron temperature coefficient of reactivity of a dilute plutonium-water solution to be negative.
