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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
D. Saphier, D. Ilberg, S. Shalev, S. Yiftah
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 660-694
Technical Paper | doi.org/10.13182/NSE77-A15209
Articles are hosted by Taylor and Francis Online.
Delayed neutron emission spectra from thermal-neutron fission of 233U, 235U, 239Pu, and 241Pu, from fast-neutron fission of 232Th, 235U, 238U, and 239Pu and from high-energy neutron (14.7-MeV) fission of 235U and 238U, for six groups of delayed neutrons are evaluated. The evaluation is based on recent measurements of delayed neutron spectra from 20 fission product isotopes. The data are presented in graphic form and are compared to directly measured equilibrium spectra whenever available. Tables with a convenient 54-energy-group structure are provided to facilitate their use in reactor calculations. The results of a limited number of two-dimensional, multigroup, transient calculations for the Clinch River Breeder Reactor core, using the newly evaluated spectra, are compared with calculations using some older spectra. The importance of the inclusion of these data in reactor dynamic calculations is evaluated.
