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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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
DOE extends Centrus’s HALEU production contract by one year
Centrus Energy has announced that it has secured a contract extension from the Department of Energy to continue—for one year—its ongoing high-assay low-enriched uranium (HALEU) production at the American Centrifuge Plant in Piketon, Ohio, at an annual rate of 900 kilograms of HALEU UF6. According to Centrus, the extension is valued at about $110 million through June 30, 2026.
E. Neymotin
Nuclear Science and Engineering | Volume 75 | Number 2 | August 1980 | Pages 133-139
Technical Paper | doi.org/10.13182/NSE80-A21302
Articles are hosted by Taylor and Francis Online.
An approximate form of the transport equation is used to investigate stationary and time-dependent neutron slowing down and propagation in the field of gravity. The approximation is based on the expansion of the δ function of the transfer function in a power series of a small parameter s, the ratio of the neutron to atom masses. It is shown that the s and s2 approximations in the stationary neutron slowing down problems are connected with Wigner and Grueling-Goertzel approximations. A simple formula is given for time-dependent neutron slowing down. The influence of the field of gravity on the operation of a reactor and on the propagation of ultra cold neutrons is studied in the point-energy approximation. Also investigated is the neutron space-energy distribution in the field of gravity.
