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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.”
Nicolas Authier, Benoît Richard, Philippe Humbert
Nuclear Science and Engineering | Volume 177 | Number 2 | June 2014 | Pages 169-183
Technical Paper | doi.org/10.13182/NSE12-111
Articles are hosted by Taylor and Francis Online.
We provide experimental data on the initiation of persistent fission chains obtained at different supercritical states, using the fast burst reactor Caliban. In many previous papers, theory has been compared mostly with initiation experiments at various superprompt critical states, whereas very few experimental data have been published on delayed supercritical states. To fill the lack of data, we have conducted three studies on the reactor at reactivities far below 0.7 $, which is one of the lowest states ever published for a similar assembly. We give a justification of the use of the gamma function to fit experimental results for the temporal distributions of waiting times and compare experiments with numerical simulations obtained with a punctual zero-dimensional Monte Carlo code and a punctual deterministic initiation code.