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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.”
Imre Pázsit
Nuclear Science and Engineering | Volume 112 | Number 4 | December 1992 | Pages 369-374
Technical Paper | doi.org/10.13182/NSE92-A23985
Articles are hosted by Taylor and Francis Online.
A new and simple derivation of the neutron transport equation is given. The approach is similar to that used in the Liouville equation and its applications to the Boltzmann equation in that it is formulated in terms of the one-particle or one-point density function, as opposed to the traditional reactor physics approach of counting neutrons in a volume of the phase-space. It makes use of the recognition that the expected number of particles in a phase cell dV is the same as the probability of finding one particle in dV. A novelty of the derivation here is that because of the linear Markovian property of the process, it is possible to derive a master (Chapman-Kolmogorov) equation for the one-particle density, that is, for the neutron density or neutron flux of the traditional transport equation. This way, the forward and the backward (adjoint) equations of neutron transport can be derived from a single master equation. The variance of the one-point distribution function is also derived, and an explicit solution is given.