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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.”
Roger L. Martz, Kevin M. Marshall
Nuclear Technology | Volume 184 | Number 2 | November 2013 | Pages 239-248
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT13-A22319
Articles are hosted by Taylor and Francis Online.
MCNP6 has been extended to include a new capability that permits tracking of neutrons and photons on an unstructured mesh (UM) embedded as a mesh universe within its constructive solid geometry capability. Our mesh geometry was created through Abaqus/CAE using its solid modeling capabilities. Monte Carlo transport results are calculated for mesh elements using a path length estimator while particles track from element face to element face on the mesh. This paper presents some performance comparisons for the initialization and calculation phases of two well-known benchmark problems using both the legacy and the UM tracking capabilities. For detailed geometries, UM initialization is always faster. For very detailed geometries where the models are comparable, the UM capability is faster than the legacy geometry capability.
