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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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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.”
T. Matsumura
Nuclear Science and Engineering | Volume 183 | Number 3 | July 2016 | Pages 407-420
Technical Paper | doi.org/10.13182/NSE15-86
Articles are hosted by Taylor and Francis Online.
The neutron escape probability from a rectangular cell is investigated for the collision probability method. Since the numerical calculation of the escape probability requires multiple integrations, resulting in a long computing time, semianalytical approximation of the multiple integrations is proposed to reduce the computing time. By approximating the result of integration in the z-direction by a polynomial expression divided into ranges, it is possible to perform the integrations in the x- and y-directions analytically. The computing time of the present semianalytical approximation is reduced by one to two orders of magnitude compared with that required for the conventional numerical integration. Moreover, a lookup escape probability table for rectangular cells calculated using the semianalytical approximation enables the calculation of the escape probability for an arbitrary rectangle with a much shorter computing time and practical precision (<0.1% error). In addition, a method of applying the semianalytical approximation and a lookup table to the collision probability calculation for an x-y geometry is discussed.
