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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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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.”
J. Chernick
Nuclear Science and Engineering | Volume 8 | Number 3 | September 1960 | Pages 233-243
Technical Paper | doi.org/10.13182/NSE60-A25804
Articles are hosted by Taylor and Francis Online.
The space-independent dynamics of a reactor controlled by xenon poisoning is investigated. For reactor periods comparable to the delay in xenon production, the reactor is stable. For shorter periods, the reactor is unstable in the neighborhood of equilibrium unless the prompt xenon yield is a large fraction of the total xenon yield. The reactor power then goes into a stable oscillation. With increase in reactivity, the oscillations are of relaxation type, having the character of a sequence of widely separated power pulses controlled by xenon poisoning. The intensity of the power pulse generally becomes excessive when the reactivity approaches the total controlled by prompt xenon. Xenon burnup is of minor importance over the region controlled by the prompt xenon yield, although it leads to flux divergence at sufficiently short reactor periods. Analytical methods are developed for treating the dynamics of the system, and the prime importance of nonlinear effects is established. The need for data on the independent yield of both Xe135 and its 15 min isomer in fission of major reactor fuels is pointed out.
