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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.
W. Haeck, B. Cochet, L. Aguiar
Nuclear Science and Engineering | Volume 171 | Number 1 | May 2012 | Pages 52-68
Technical Paper | doi.org/10.13182/NSE10-99
Articles are hosted by Taylor and Francis Online.
To take the production of isomeric states into account during the irradiation of a material, a depletion code needs the proper isomeric branching ratio s for every isomeric state s produced in a reaction. The composition of some nuclides such as, for example, 238Pu and some Cm isotopes is quite sensitive to the value of the isomeric branching ratio for the 241Am neutron capture reaction. Existing depletion codes use constant burnup-independent values for the isomeric branching ratio data, which were calculated in advance for a particular type of spectrum (e.g., pressurized water reactor, boiling water reactor, or fast reactor systems). In this paper, we propose a burnup-dependent treatment using evaluated nuclear data from ENDF files as a function of the irradiation history. This treatment has been implemented into the VESTA Monte Carlo depletion code using both the multigroup binning approach and Monte Carlo estimators. The validity and usefulness of this new treatment has been demonstrated using experimental data from the MALIBU program and has shown that it improves the prediction of 242mAm when using JEFF 3.1 data. It is also shown that more work is required on the measurement and evaluation of the cross-section data for the Am isotopes in general and the energy-dependent 241Am branching ratio in particular to improve the results of depletion calculations.
