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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Stefano Terlizzi, Dan Kotlyar
Nuclear Science and Engineering | Volume 193 | Number 9 | September 2019 | Pages 948-965
Technical Paper | doi.org/10.1080/00295639.2019.1583948
Articles are hosted by Taylor and Francis Online.
This paper presents the theoretical foundations and the practical implementation of the Fission Matrix Decomposition (FMD) method. The FMD method is a hybrid technique for the rapid and accurate solution of the criticality transport problem in highly heterogeneous media. The method relies on a two-stage sequence, conceptually similar to the approach adopted by production codes, such as CASMO/SIMULATE. First, a database of local fission matrices and coupling coefficients is generated through Monte Carlo calculations. The database is then used to reconstruct the full fission matrix, from which multiplication factor and fission source distribution are computed with a deterministic eigensolver. The FMD method is here tested against two stylized problems: (1) the pressurized water reactor unit-cell problem and (2) the resource-renewable boiling water assembly problem. The accuracy and computational efficiency of the FMD method are compared against the continuous-energy Monte Carlo Fission Source Iteration method, the Fission Matrix-Based Monte Carlo approach, and the lattice-diffusion approximation. For the analyzed cases, the FMD was 100 times faster than diffusion, while maintaining transport accuracy with a mean absolute percent error lower than 1% on the fission source distribution and difference in multiplication factor below 7 pcm.
