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Division Spotlight
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
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
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
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.
