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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.”
J. W. Allen, J. C. Robinson, N. J. Ackermann, Jr.
Nuclear Technology | Volume 22 | Number 3 | June 1974 | Pages 315-322
Technical Paper | Reactor | doi.org/10.13182/NT74-A31416
Articles are hosted by Taylor and Francis Online.
A study was made to determine the uncertainty in subcritical reactivity as inferred from inverse kinetics rod drop experiments (using the three-point method) due to the statistical uncertainty inherent in the observed count rate of the neutron sensor. The two methods employed were a classical propagation of error analysis, and an analysis of simulated repeated rod drops, with an assumption that the uncertainty in reactivity was due to the detection process itself for both techniques, To test the analysis methods, the reactivity uncertainties for various experimental rod drop data sets were computed by both methods. There was excellent agreement of the results. The propagation of error analysis may be used on three-point subcriticality measurements to provide an experimenter with an index to the statistical reliability of the inferred reactivity estimate.