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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.
E. Friedman
Nuclear Science and Engineering | Volume 19 | Number 2 | June 1964 | Pages 203-208
Technical Paper | doi.org/10.13182/NSE64-A28910
Articles are hosted by Taylor and Francis Online.
A new method for measuring neutron thermalizaton parameters that was proposed on theoretical grounds is tested experimentally for H2O. The characteristic thermalization parameters in the present formulation are where are Laguerre polynomials of order unity and degree i and T is the temperature of the system expressed in energy units. The present experimental results for H2O can be described using one parameter. The result is γ11 = (0.210 ± 0.026)cm-1 for 23 C. The value of this parameter as derived from diffusion-cooling measurements lies in the range of 0.4cm-1 to 0.8cm-1. A possible explanation for this discrepancy is given. The value of γ11 as calculated on the basis of Nelkin's model is about four times higher than the present result.
