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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
M. P. Fricke, J. M. Neill
Nuclear Science and Engineering | Volume 50 | Number 4 | April 1973 | Pages 392-397
Technical Note | doi.org/10.13182/NSE73-A26576
Articles are hosted by Taylor and Francis Online.
The neutron spectrum and criticality of ZPR-3 Assembly 11 have been calculated using estimated cross sections for the mU(n, γn’) reaction. Inclusion of this reaction markedly improves agreement between the measured and calculated spectra, and it also decreases the calculated criticality by 0.62%. This change in criticality can be compensated for by lowering the 238U capture cross section from the ENDF/B-III values to those of a recent microscopic measurement. These and other ramifications of the (n,γn’) reaction in fast reactor assemblies are discussed.