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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.”
F. B. Simpson, W. H. Burgus, J. E. Evans, H. W. Kirby
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 243-249
Technical Paper | doi.org/10.13182/NSE62-A26064
Articles are hosted by Taylor and Francis Online.
The total cross section for Pa231 was measured from 0.01 ev to 2 kev, with the use of the Materials Testing Reactor fast chopper with resolutions from 0.040 to 2.0 µsec/meter. The Breit-Wigner resonance parameters have been obtained for the resonances below 11.0 ev. These measurements were made with samples prepared from 0.558 gm of Pa2O5. Weighting the level spacings inversely as 2J + 1 gives the average observed level spacings per spin state of 0.72 and 1.2 ev. This is one of the smallest spacings observed in any isotope. The average parameters give a value of 0.63 × 10−4 for the s-wave neutron strength function . A linear least squares fit to the data between 0.015 and 0.03 ev gives a value of 211 ± 2 barns for the thermal cross section. The resonance absorption integral (for neutrons with energies > 0.1 ev) is 1560 ± 55 barns, with a contribution of approximately 65% from the 0.396 ev resonance.
