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Division Spotlight
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.
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.
P. L. Reeder, R. A. Warner
Nuclear Science and Engineering | Volume 79 | Number 1 | September 1981 | Pages 56-64
Technical Paper | doi.org/10.13182/NSE81-A19042
Articles are hosted by Taylor and Francis Online.
Average energies of the delayed neutron spectra from 34 precursors have been compiled from the literature to give a set of best values. Average energies of six-group and equilibrium spectra are calculated by summing weighted values of the individual precursors. These calculated average energies are in reasonable agreement with the rather limited experimental data. Equilibrium delayed neutron spectra are calculated by summing spectra for individual precursors. The calculated equilibrium spectra are then compared to an approximate spectrum based on a Maxwellian distribution with just one parameter, the average energy. Sets of experimental spectra for individual precursors measured at two different laboratories are compared. The Maxwellian shape gives reasonable agreement with one set. The other set has more neutrons at low energy and does not fit a Maxwellian shape.
