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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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ANS joins others in seeking to discuss SNF/HLW impasse
The American Nuclear Society joined seven other organizations to send a letter to Energy Secretary Christopher Wright on July 8, asking to meet with him to discuss “the restoration of a highly functioning program to meet DOE’s legal responsibility to manage and dispose of the nation’s commercial and legacy defense spent nuclear fuel (SNF) and high-level radioactive waste (HLW).”
R. J. Cerbone, R. E. Slovacek, E. R. Gaerttner
Nuclear Science and Engineering | Volume 30 | Number 1 | October 1967 | Pages 75-84
Technical Paper | doi.org/10.13182/NSE67-A17244
Articles are hosted by Taylor and Francis Online.
Position-dependent thermal spectra have been measured in a paraffin-moderated 235U multiplying assembly using two independent methods. Steady-state spectra were obtained with the time-of-flight technique employing a 24.40-m flight in conjunction with the Rensselaer Polytechnic Institute linear accelerator; asymptotic (in time) spectra were obtained with the pulsed-LINAC chopper technique. A new technique was developed to monitor the source intensity with a tracking reliability of ± 1.5%. The measured spectra are compared to a series of DTF-IV transport calculations using a P1 kernel and P1 source; the spatial source was obtained from a transport calculation. The spectrum calculations were performed with a polyethylene kernel utilizing either the Goldman model or the Koppel-Young four-oscillator model. The experimental spectra are generally in closer (better than 5%) agreement with calculations using the Goldman kernel than with those using the Koppel-Young kernel. This result is consistent with the total cross section of polyethylene measured by Armstrong.