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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.
Dermott E. Cullen
Nuclear Science and Engineering | Volume 55 | Number 4 | December 1974 | Pages 387-400
Technical Paper | doi.org/10.13182/NSE74-3
Articles are hosted by Taylor and Francis Online.
The probability table method, developed for Monte Carlo calculations in the region of unresolved neutron resonances, is demonstrated to be of general use in neutron transport studies since the Boltzmann equation involved can be derived and solved by analogy to multigroup methods. Since the resulting equations can be cast into a form identical to that of the multigroup equations, they can be solved by existing multigroup transport codes. From a set of probability tables and spatially independent, unshielded, neutron cross sections, the method yields correct selfshielding effects, such as equivalent, spatially dependent, multigroup cross sections. Extension of the method and the use of probability tables outside the unresolved region are discussed.