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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.
Wendell C. Demarcus
Nuclear Science and Engineering | Volume 5 | Number 5 | May 1959 | Pages 336-337
Technical Paper | doi.org/10.13182/NSE59-A25606
Articles are hosted by Taylor and Francis Online.
An integral equation is derived for the function giving the average number of collisions required to thermalize neutrons by elastic collisions with nuclei of relative mass M. An asymptotic solution is obtained which corrects the customary result by between and 1 collision (depending on M). Numerical results for small lethargy increments are presented for the cases M = 2 and M = 235.
