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ANS Student Conference 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.”
Argala Srivastava, K. P. Singh, Amod Kishore Mallick, Umasankari Kannan, S. B. Degweker
Nuclear Science and Engineering | Volume 193 | Number 9 | September 2019 | Pages 1044-1053
Technical Note | doi.org/10.1080/00295639.2019.1596721
Articles are hosted by Taylor and Francis Online.
The use of the Monte Carlo (MC) method for obtaining higher modes is an active area of current research. The method faces several difficulties in its implementation for practical problems. The study of simpler models in this context may be expected to provide insights into some of these problems. This technical note describes the development of a fission matrix algorithm based on the diffusion theory MC model to obtain fundamental and higher λ eigenvalues and eigenvectors (modes) of a reactor. A method for estimating variance in the estimated eigenvalues using first-order perturbation theory is also developed. The algorithm has been implemented in the space-time–kinetics MC code KINMC. The performance of the method for calculating higher eigenvalues and higher eigenvectors has been verified through comparison of the eigenvalues thus obtained with the results of other deterministic codes. Results of computation of eigenvalues and eigenvectors up to six modes are presented in this technical note.
