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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.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
X-energy receives federal tax credit for TRISO fuel facility
Advanced reactor company X-energy has been awarded $148.5 million in tax credits under the Inflation Reduction Act for construction of its TRISO-X fuel fabrication facility in Oak Ridge, Tenn.
Li Mao, J. P. Both, J. C. Nimal
Nuclear Science and Engineering | Volume 130 | Number 2 | October 1998 | Pages 226-238
Technical Paper | doi.org/10.13182/NSE98-A2002
Articles are hosted by Taylor and Francis Online.
The coefficients of a truncated Legendre series are usually used in multigroup cross-section sets to treat the angular distribution for a group-to-group scattering event. Fine energy meshes and low-order Legendre expansions result in negative values in the corresponding multigroup Legendre expansions; therefore, special transfer matrix treatments for multigroup cross sections are needed.The difficulties of the truncated Legendre series representation in treating multigroup transfer are explained. In TRIMARAN-II, two existing standard methods, the equally probable step function (EPSF) representation and the discrete angle representation, which are based on preservation (at least approximately) of the first moments, are studied. The discrete angle representation has the advantage of accurately preserving the moments, but it may cause ray effects; the EPSF representation can eliminate ray effects, but it is not suitable for the treatment of the transfer matrix for material mixtures, because both forward- and backward-peaked scattering are present in this kind of cross section. A new method, the nonequally probable step function (NEPSF) representation, which combines the advantages of both the discrete angle and EPSF representations, is introduced. It can eliminate ray effects and accurately preserve the moments. The conjugate gradient method, powerful for solving multidimensional minimization problems, is used to obtain both the EPSF and NEPSF representations. A problem of neutron transmission in a hydrogenous material is used to compare the three representations. Comparisons of the TRIMARAN-II results with the three representations to those of the TRIPOLI-4 pointwise cross-section Monte Carlo code are given.