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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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. R. Alexander, M. S. Krick
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 627-635
Technical Paper | doi.org/10.13182/NSE77-A15206
Articles are hosted by Taylor and Francis Online.
The total delayed neutron yield from 235U was calculated as a function of the energy of the neutron inducing fission. The calculations (based on fission data and fission systematics) extend from thermal to 15-MeV neutron energies. The energy-dependent delayed neutron calculations are generally consistent with experimental results from thermal to 14-MeV neutron energies. Delayed neutron yields per 104 fissions of 168.7 ± 16.7, 178.2 ± 17.2, and 88.9 ± 10.0 were obtained at thermal, fission-spectrum, and 15-MeV neutron energies, respectively. The energy dependence of the odd-even effect in the fission charge distribution was found to partially account for the near constant yield observed below 5-MeV neutron energy, as well as the rapid decrease in yield observed at the second-chance fission threshold.