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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
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.