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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.
G. C. Pomraning
Nuclear Science and Engineering | Volume 52 | Number 1 | September 1973 | Pages 144-145
Technical Note | doi.org/10.13182/NSE73-A23298
Articles are hosted by Taylor and Francis Online.
Consider one-speed neutron transport in an infinite medium. Let a neutron be released from the origin at time zero. In a recent paper, a probabilistic argument was used to derive an exact expression, for an arbitrary scattering law, giving the neutron’s mean square distance from the origin as a function of time. This result can be derived in a much simpler manner by merely forming the appropriate spatial and angular moments of the transport equation.