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ANS Student Conference 2025
April 3–5, 2025
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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
M. CANTWELL, M. GOLDSMITH
Nuclear Science and Engineering | Volume 12 | Number 4 | April 1962 | Pages 490-497
Technical Paper | doi.org/10.13182/NSE62-A26096
Articles are hosted by Taylor and Francis Online.
Measured fast fission activations of depleted U238 foils in thin clean critical slabs are compared with theoretical predictions made using the P-1 and P-3 approximations. Various methods of analyzing fast activation experiments are considered. Finally, the effect of the P-3 approximation in the fast groups on the thermal flux is studied by comparing Mn wire activations out to 50 cm in the reflector of a thin clean critical slab with several theoretical calculations. It is found, as would be expected, that the deviations of the calculated P-1 activations from experiment increase as the observer moves farther out into the reflector. The use of the P-3 approximation gives marked improvement. As regards eigenvalues, experience in the analysis of thin clean critical slabs with highly enriched fuel and metal-to-water volume ratios from 1 to 1.7 indicates that use of the P-3 approximation in the first few fast groups results in an increase in eigenvalue of more than a per cent.