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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.”
Janet Seltzer, W. K. Firk
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 415-419
Technical Paper | doi.org/10.13182/NSE74-A23372
Articles are hosted by Taylor and Francis Online.
The total neutron cross section of sodium has been measured in the vicinity of the 2.8-keV resonance with the high-resolution time-of-flight spectrometer associated with the Yale University 70-MeV Electron Linear Accelerator. The spin of the resonance is unambiguously identified to be J = 1 . A least-squares analysis of the cross section has been carried out up to an energy of 50 keV using a model that takes into account the effects of local and distant levels. The observed total cross section is well described throughout the entire range with a spin-independent interaction radius of 5.8 fm and with reasonable values of the R functions (distant level effects) for both spin states. The resonance energy, the neutron width, and the effective nuclear radii derived from the analysis are, respectively, ER = 2805 ± 30 eV, ΓnR = 376 ± 15 eV, aJ =1 = 5.3 fm, and aJ=2(E) = 5.7 + [2 × 108/(E + 18500)2] fm.
