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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.”
Dean Wang, Tseelmaa Byambaakhuu
Nuclear Science and Engineering | Volume 195 | Number 12 | December 2021 | Pages 1347-1358
Technical Note | doi.org/10.1080/00295639.2021.1924048
Articles are hosted by Taylor and Francis Online.
It has been well known that the analytic neutron transport solution tends to the analytic solution of a diffusion problem for optically thick systems with small absorption and source. The standard technique for proving the asymptotic diffusion limit is constructing an asymptotic power series of the neutron angular flux in small positive parameter , which is the ratio of a typical mean free path of a particle to a typical dimension of the problem domain. In this paper, first, we provide an analysis of the asymptotic properties of the SN transport eigenvalues. Then, we show that the analytical SN transport solution satisfies the diffusion equation in the asymptotic diffusion limit based on a recently obtained closed-form analytical solution to the one-dimensional monoenergetic SN neutron transport equation. The boundary conditions for the diffusion equation are discussed.