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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.
A. Z. Akcasu, M. M. R. Williams
Nuclear Science and Engineering | Volume 148 | Number 3 | November 2004 | Pages 403-413
Technical Paper | doi.org/10.13182/NSE04-A2466
Articles are hosted by Taylor and Francis Online.
Statistical aspects of particle transport in spatially random media in one dimension are studied analytically using the dichotomic and the binomial binary random processes as two models for the spatial randomness in the particle density. The mean and the variance of the flux are expressed in terms of the moments <U(x)n> of the stochastic propagator U(x) = exp[-z(x)], where z(x) is the optical path length. The moments <U(x)n> are rigorously calculable with the above random processes. In the case of semi-infinite media, the calculations are carried out using the one-dimensional, one-speed transport equation. In finite media, one-speed diffusion theory is used to calculate the mean and variance of the flux within the slab. In particular, the statistics of the albedo and the exit current are investigated. The mean of the local reaction rates within the slab is also calculated.