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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.
Takashi Nakamura, Toshiso Kosako
Nuclear Science and Engineering | Volume 77 | Number 2 | February 1981 | Pages 168-181
Technical Paper | doi.org/10.13182/NSE81-A21351
Articles are hosted by Taylor and Francis Online.
The skyshine of monoenergetic neutrons directed upward from sources both as a vertically collimated beam and as a point isotropic cone fixed on the ground has been calculated systematically by a Monte Carlo method for distances up to ∼2 km from the source. The energy of the neutrons ranged from 14 MeV to thermal. The calculated skyshine spectra approach an approximate equilibrium having an approximate 1/E dependence in the keV region beyond about a few hundred metres from the source. The total neutron flux Φ(r) and dose D(r) at a distance r from a source are well represented by a simple formula, and D(r) = QDexp(-r/λD)/r, and the constants , and λD are only dependent on the source-neutron energy. In respect to the dependence of , and QD on the upward aperture, θs, of the cone source and λD change very little with θs, but and QD increase with θs, when θs is larger than 30 deg. This simple formula was applied to evaluate the experimental results of skyshine neutron doses from a fast-neutron source-reactor facility and showed nice agreement.
