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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.
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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
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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
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.
L. M. Gomes, P. N. Stevens
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1996-2000
Neutronic | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29634
Articles are hosted by Taylor and Francis Online.
This work revisits the problem of ray effects in discrete ordinates calculations that frequently occurs in two- and three-dimensional systems which contain isolated sources within a highly absorbing medium. The effectiveness of using a first collision source or a second collision source are analyzed as possible remedies to mitigate this problem. The first and second scattering sources are calculated with the Monte Carlo method that is intrinsically free from ray effects. The scattering source is then coupled to a discrete ordinates code for a hopefully ray-effect-free transport calculation. The scattering source generated by the Monte Carlo method is distributed throughout geometry space and therefore would be less likely to produce ray effects in the discrete ordinates calculation. This remedy for the ray effect is demonstrated for a point source in cylindrical geometry and for a localized distributed source in X-Y geometry. The first collision and second collision sources are generated by three-dimensional Monte Carlo calculations and enables its application to a variety of source configurations and the results can be coupled to a two- or three-dimensional discrete ordinates transport code. The Monte Carlo computational time and precision requirements constitute some limitations but these are minimized since the Monte Carlo transport is performed only up to the first collision.