ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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Nuclear Science and Engineering
February 2025
Nuclear Technology
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Latest News
IAEA’s nuclear security center offers hands-on training
In the past year and a half, the International Atomic Energy Agency has established the Nuclear Security Training and Demonstration Center (NSTDC) to help countries strengthen their nuclear security regimes. The center, located at the IAEA’s Seibersdorf laboratories outside Vienna, Austria, has been operational since October 2023.
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.
