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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.
B. Goel
Nuclear Science and Engineering | Volume 69 | Number 1 | January 1979 | Pages 99-104
Technical Note | doi.org/10.13182/NSE79-A21291
Articles are hosted by Taylor and Francis Online.
It is well established that helium formed in stainless steel by various (n,α) processes has a pronounced effect on its mechanical and dimensional properties. The anomalous production of helium in nickel-based alloys is known to take place via the two-step process: 58Ni(n,γ)59Ni(n,α)56Fe. For thermal neutrons, the 59Ni(n,α)56Fe cross section used to calculate the helium production differs strongly from the value obtained by the direct measurements of this cross section. In this Note, this discrepancy is discussed, and a value of 12.5 ± 1 b based on direct measurements is recommended for future calculations. For fast neutrons, the contribution due to the two-step process has been ignored in the past. It is demonstrated that this contribution is substantial, and it gains in importance as the neutron fluence increases. It is further shown that the usual practice to relate helium production data to thermal- and fast-neutron fluence is inadequate. The details of the neutron spectrum and the cross section are necessary to reliably predict the helium production rate.
