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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
R. J. Cerbone, R. E. Slovacek, E. R. Gaerttner
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 75-84
Technical Paper | doi.org/10.13182/NSE67-A17244
Articles are hosted by Taylor and Francis Online.
Position-dependent thermal spectra have been measured in a paraffin-moderated 235U multiplying assembly using two independent methods. Steady-state spectra were obtained with the time-of-flight technique employing a 24.40-m flight in conjunction with the Rensselaer Polytechnic Institute linear accelerator; asymptotic (in time) spectra were obtained with the pulsed-LINAC chopper technique. A new technique was developed to monitor the source intensity with a tracking reliability of ± 1.5%. The measured spectra are compared to a series of DTF-IV transport calculations using a P1 kernel and P1 source; the spatial source was obtained from a transport calculation. The spectrum calculations were performed with a polyethylene kernel utilizing either the Goldman model or the Koppel-Young four-oscillator model. The experimental spectra are generally in closer (better than 5%) agreement with calculations using the Goldman kernel than with those using the Koppel-Young kernel. This result is consistent with the total cross section of polyethylene measured by Armstrong.
