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The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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.”
H. L. McMurry and G. J. Russell and R. M. Brugger
Nuclear Science and Engineering | Volume 25 | Number 3 | July 1966 | Pages 248-260
Technical Paper | doi.org/10.13182/NSE66-A17832
Articles are hosted by Taylor and Francis Online.
Experimental data on the slow-neutron ( < 0.1 eV) scattering of room-temperature water have been obtained using the velocity selector at the Materials Testing Reactor. The data agree with the results of Haywood obtained using a slow-neutron velocity selector, with the results of Kottwitz and Leonard obtained using a triple-axis spectrometer, and with the results of Kirouac obtained using a linear accelerator plus phased chopper. There are marked differences from the results of Sakamoto and co-workers, who used cold neutrons and a rotating crystal spectrometer. An extension of the Nelkin model has been devised that gives calculated results in good agreement with the MTR data, whereas the Nelkin model generally gives poor agreement. The new model treats water as a mixture of 10% of free molecules and 45% each of two aggregates in which the effective masses for H scattering are 75 and 150. Each aggregate has a set of vibrational modes with energies distributed in the range 0 < E ≤ 0.125 eV, and each H2O molecule exhibits the internal modes with characteristic energies of 0.2, 0.45, and 0.46 eV. The amplitudes of the low-energy vibrations are selected so the calculated scattering agrees with the Materials Testing Reactor data. Total cross sections calculated on the new model and the Nelkin model agree quite well with the data. The new model gives values of the average cosine of the scattering angle that are closer to the data than those calculated by the Nelkin model, but the calculated results are always higher than the data. At very low neutron energies, the present Nelkin model calculations give total cross sections that are lower than those reported by Koppel and Young using essentially the same model. The reason for this is not known.