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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.
Ken Nakajima, Masanori Akai, Takenori Suzaki
Nuclear Science and Engineering | Volume 116 | Number 2 | February 1994 | Pages 138-146
Technical Paper | doi.org/10.13182/NSE94-A21489
Articles are hosted by Taylor and Francis Online.
The modified conversion ratio is defined as the ratio of 238U captures to total fission. Gamma-ray spectrometry of irradiated fuel rods has been introduced to measure this quantity in two types of water-moderated low-enriched UO2 cores: the standard core, called the 1.42S core, and a tight-lattice core, called the 0.56S core. The water moderator-to-fuel volume ratios Vm/Vf of the cores are 1.420 and 0.564, respectively. As no activation foil is used in this method, no corrections are needed for the neutron self-shielding and neutron flux depression that are caused by such a foil. Instead, the gamma-ray self-shielding effect due to the fuel rod must be corrected. The modified conversion ratio is measured by this method are 0.457 for the 1.42S core and 0.724 for the 0.56S core. The errors in the experimental results are estimated to be∼3%. Computer analyses using the VIM continuous-energy Monte Carlo code with the JENDL-2 library show that the calculated value is ∼6% larger than the experimental one for the tight-lattice 0.56S core.
