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Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
Mekiel Olguin, Christopher Perfetti, Forrest Brown
Nuclear Science and Engineering | Volume 196 | Number 11 | November 2022 | Pages 1323-1332
Technical Paper | doi.org/10.1080/00295639.2022.2087831
Articles are hosted by Taylor and Francis Online.
The dominance ratio is the ratio of the first higher-order mode eigenvalue of a system to the fundamental eigenvalue, k1/k0. It can be used to determine how well coupled the neutrons in a multiplying system are, as well as the computational difficulty of the power iteration method in a Monte Carlo simulation. The purpose of this study is to investigate the University of New Mexico’s (UNM’s) AGN-201M reactor’s unusually low dominance ratio of 0.632. The AGN-201M reactor is a small, thermal spectrum reactor located at the UNM. It is moderated by polyethylene, reflected by graphite, and uses fuel comprised of uranium microspheres embedded in polyethylene plates that are separated by an aluminum baffle. The investigation included a parametric study of the reactor’s fuel geometry, fuel density, and reflector thickness to examine their impact on the reactor’s dominance ratio. In addition, neutronically similar systems were examined to identify common causes for systems with low dominance ratios. The reason for the small dominance ratio of the AGN-201M reactor when compared to large thermal reactors was determined to be because of its size and fuel plate composition. The reflector’s effect on the dominance ratio is small in comparison to the other factors but was found to have a nonzero effect. Furthermore, the AGN-201M was found to have a significantly lower dominance ratio than systems with which it shares a very high ( > 95%) degree of neutronic similarity. However, the two most similar systems were close in size to the core of the AGN-201M reactor and were moderated with polyethylene as well.