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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.”
W. A. Houlberg
Fusion Science and Technology | Volume 44 | Number 2 | September 2003 | Pages 518-521
Technical Paper | Fusion Energy - Plasma Engineering, Heating, and Current Drive | doi.org/10.13182/FST03-A389
Articles are hosted by Taylor and Francis Online.
The transport and net loss of cyclotron radiation for burning plasmas represented by the ITER, FIRE and IGNITOR designs are assessed using the CYTRAN radiation transport code. Although cyclotron radiation might be expected to be a bigger issue in the higher field devices (FIRE and IGNITOR), the reference operating conditions in those devices are at lower temperatures so that the relative importance is nearly constant for all three. At the reference operating conditions for each of these devices, the net energy loss from cyclotron radiation is about 10% of the alpha power, and the axial loss is typically about 15% of the local alpha power density. If the same fusion power is generated at higher temperature and lower density than the reference operating points (as may be the case in advanced confinement modes), both the net and axial loss fractions strongly increase and are more competitive with other energy transport processes. The increase is much stronger for the high field devices where the axial loss can approach the local alpha energy production rate for T(0) ~ 30 keV. However, if the temperature increases at constant density (as in a thermal excursion), cyclotron radiation loss remains an almost constant fraction of the alpha production rate. This implies that it will not make a significant contribution to thermal stabilization. However, these and other calculations of cyclotron radiation transport are sensitive to assumptions of reflection, plasma geometry and profile shapes. Therefore, the effect of cyclotron radiation on operating conditions and burn dynamics will undoubtedly be a generic issue that any burning plasma will have to address.