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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.
R. Gwin
Nuclear Science and Engineering | Volume 61 | Number 3 | November 1976 | Pages 428-431
Technical Note | doi.org/10.13182/NSE76-A26929
Articles are hosted by Taylor and Francis Online.
The analysis of critical volumes of aqueous homogeneous solutions of uranium to aid in defining the 2200 m/sec neutron parameters for ENDF/B has been examined. The parameters for 233U and 235U are constrained by relating to the constant K obtained from the analysis of the critical systems. Here K is directly proportional to the hydrogen capture cross section at 2200 m/sec. This Note suggests that the capture cross section of hydrogen be removed from K and that a new constant K/σaH be defined by the critical systems. This new constant is the hydrogen-to-uranium ratio for an infinite critical system populated with neutrons having a Maxwellian energy distribution.