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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.
M. M. Bretscher, W. C. Redman
Nuclear Science and Engineering | Volume 39 | Number 3 | March 1970 | Pages 368-378
Technical Paper | doi.org/10.13182/NSE70-A19997
Articles are hosted by Taylor and Francis Online.
The effective capture-to-fission ratio has been measured for 239Pu and 235U in a low flux fast-reactor spectrum by the reactivity-reaction-rate technique. A 252Cf source and a 6Li absorber were used to measure the relative importance of fission and absorbed neutrons, respectively. The measurements were made in Assembly 24 of ZPR-9 which was designed to produce a neutron spectrum that emphasized fission and capture events in the 0.1 to 25 keV range. For 239Pu and 235U the measured values, corrected to infinite sample dilution, were 0.516 ± 0.040 and 0.337 ± 0.029, respectively. Corresponding integral alpha values calculated from ENDF/B were 0.352 and 0.346. The experimental value for 239 is in reasonable agreement with calculations based on recent differential data obtained by both the Oak Ridge-Rensselaer and the United Kingdom groups. These calculations yielded 239Pu alpha values of 0.466 (ORNL-RPI) and 0.471 (UK).
