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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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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).”
Charles Erwin Cohn
Nuclear Science and Engineering | Volume 6 | Number 4 | October 1959 | Pages 284-287
Technical Paper | doi.org/10.13182/NSE59-A28845
Articles are hosted by Taylor and Francis Online.
In reactors having D2O or Be moderators, the photoneutrons produced by gamma rays from long-lived fission products give rise to transient effects which could introduce appreciable errors into various types of reactivity measurements. This paper presents digital computer calculations of these effects in D2O for criticality measurements, subcritical multiplication measurements, rod drops, and rising period measurements. It is found that in some cases appreciable errors are possible even after one hour waiting periods. Since the Be photoneutron data cannot be resolved into groups, calculations for Be could not be done. However, the nature of the effects that could be expected is discussed.