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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.”
Charles N. Kelber, Philip H. Kier
Nuclear Science and Engineering | Volume 24 | Number 4 | April 1966 | Pages 389-393
Technical Paper | doi.org/10.13182/NSE66-A16409
Articles are hosted by Taylor and Francis Online.
As suggested by Brissenden, it is possible to analyze the reaction rate in the unresolved resonance region by generating sets of random resonance parameters that have the correct statistical properties. Since each set of parameters is itself a random variable, an estimate of the probable error in an average-group cross section or reaction rate can be made by averaging over many random sets. This we have done for a mixture representative of fast breeder reactors and for the energy range 700 to 900 eV. This region is a typical one for studying the Doppler effect. If we make the assumption (a great oversimplification) that the response in this small energy band is typical, not only for the mean but also for the variance, then we would conclude that, if all fine groups (of width 200 eV) have the same weight, the probable error in the fissile component of the Doppler coefficient is about equal to its mean value. For the fine group itself, the probable error in the difference in the relative changes of the fission and the absorption rates is about ten times the mean value.
