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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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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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.
John C. Vigil
Nuclear Science and Engineering | Volume 29 | Number 3 | September 1967 | Pages 392-401
Technical Paper | doi.org/10.13182/NSE29-03-392
Articles are hosted by Taylor and Francis Online.
A method based on analytic continuation, which is well suited for fast digital computer application, has been applied to the point reactor kinetics equations. The most important characteristic of the method is that it yields an analytic criterion for the magnitude of the time step. This criterion is such that the time step automatically expands or contracts, depending on the behavior of the function within each interval. The use of this criterion to determine the time step guarantees that the fractional error in the results increases, at most, linearly with the number of time steps. Furthermore, the magnitude of the time step determined from this criterion can be much larger than the prompt-neutron generation time. Approximate solutions by this method were compared with some analytic solutions to the reactor kinetics equations, and the error accumulation was found, in all cases, to be within the limits predicted by the theory. Comparisons were also made with experimental transients in the Godiva and SPERT I reactors. The approximate results were found to agree well with experiment in the range of reactivity inputs where the feedback model used is valid. In a comparison with another numerical method (RTS code), analytic continuation was found to be 25 times faster.