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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.”
Megha Bhike, B. J. Roy, A. Saxena, R. K. Choudhury, S. Ganesan
Nuclear Science and Engineering | Volume 170 | Number 1 | January 2012 | Pages 44-53
Technical Paper | doi.org/10.13182/NSE10-63
Articles are hosted by Taylor and Francis Online.
Neutron-induced reaction cross sections for the reaction 232Th(n, )233Th have been measured at neutron energies of 1.6 ± 0.03 MeV, 2.2 ± 0.03 MeV, 3.0 ± 0.03 MeV, and 3.7 ± 0.03 MeV. We have also measured cross sections for the reactions 98Mo(n, )99Mo, 186W(n, )187W, 115In(n, )116m1In, and 92Mo(n, p)92mNb at a neutron energy of 3.2 ± 0.03 MeV. The 7Li(p, n)7Be reaction was used as the neutron source with the proton beam from the 14-MV Pelletron accelerator, Mumbai, and the standard off-line gamma counting method was followed for activation measurement. The present measurements supplement the existing data and provide new data in the neutron energy range where no results are available. While the cross-section values for the 98Mo(n, )99Mo and 186W(n, )187W reactions are reported for the first time, the data for 92Mo(n, p)92mNb exists with a large discrepancy between the two available data sets. For the 115In(n, )116m1In reaction, our measurement at 3.2 MeV is an additional data point where there exists significant disagreement among the data measured by different groups. The measurements are performed relative to the 115In(n, n′)115mIn and 197 Au(n, )198 Au cross sections of International Reactor Dosimetry File 2002. Detailed theoretical calculations using the statistical model code EMPIRE-II (latest version EMPIRE-2.19) have been performed. Good agreement with the present data along with the existing data set has been obtained by suitable adjustment of the level density parameter for all the systems. The experimental and theoretical results have been compared with the recent evaluations of ENDF/B-VII.0, JENDL-4.0, and JEFF-3.1.