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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
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.
Claude Mounier, Pietro Mosca
Nuclear Science and Engineering | Volume 179 | Number 2 | February 2015 | Pages 130-147
Technical Paper | doi.org/10.13182/NSE13-63
Articles are hosted by Taylor and Francis Online.
The fast neutron fluence is an important parameter for the reactor pressure vessel (RPV) lifetime. The uncertainty estimation of this parameter is crucial to manage the RPV with a suitable safety margin. This work focuses on a facet of the problem that concerns the uncertainty contribution of the spectrum of the fission source for different burnups in a thermal neutron reactor. The main goal of this paper is to assess the effect of a possible uncertainty correlation among the spectra of the fissile nuclei, involved in the fission source, on the response uncertainty. Two main simplifications are assumed to reduce the complexity of the problem. The first simplification concerns the geometry of the transport problem that is chosen to calculate as fast as possible the sensitivities and the different responses. The second simplification is related to the way by which one can take into account the correlations among spectra of different fissile nuclei. Simple ENDF-6 models of the fission spectrum (Maxwell, Watt, and simplified Madland-Nix) are used to define correlations among the fissile spectra through the mean neutron energy of the prompt fission spectrum. Results are given to quantify the effect of these postulated correlations on response uncertainties and are compared to the ones using JENDL-4.0 covariances.