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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. M. R. Williams
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 260-270
Technical Paper | doi.org/10.13182/NSE64-A18326
Articles are hosted by Taylor and Francis Online.
An exact solution to the energy-dependent Milne problem for isotropic scattering has been obtained using a simple separable scattering kernel. The extrapolation distance and angular distribution at the surface of the half-space have been calculated using the free-gas scattering cross sections. A further calculation for a very narrow kernel shows that the extrapolation distance is insensitive to the inelastic part of the scattering kernel, but depends mainly on the energy dependence of the mean free path. The results have been compared with numerical work obtained from the THERMOS code and thus provide a measure of the accuracy of THERMOS for this type of problem. The results also give physically reasonable bounds on the extrapolation distance and angular distributions.
