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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.
L. Green, J. A. Mitchell, N. M. Steen
Nuclear Science and Engineering | Volume 52 | Number 3 | November 1973 | Pages 406-412
Technical Note | doi.org/10.13182/NSE73-A19488
Articles are hosted by Taylor and Francis Online.
The 233U fission neutron spectrum has been measured by pulsed-beam time-of-flight techniques from 0.8 to 10 MeV. Above ≈2 MeV, the data were found, within statistics, to be adequately represented by either the model in the ENDF/B-III file or a best fit Maxwellian distribution with nearly the same average energy. At lower energy, the data appear to follow the ENDF/B representation somewhat more closely. The fit of a Maxwellian distribution to the 233U data yielded an average “temperature” parameter of 1.34 ± 0.02 MeV, where the error includes both statistical and systematic uncertainties. A similar fit to data taken for a 235U sample yielded a temperature parameter of 1.31 ± 0.03 MeV; however, the best estimated difference in temperature is 16 ± 6 keV.