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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).”
Albert L. Hanson, Hans Ludewig, David J. Diamond
Nuclear Science and Engineering | Volume 153 | Number 1 | May 2006 | Pages 26-32
Technical Paper | doi.org/10.13182/NSE06-4
Articles are hosted by Taylor and Francis Online.
The prompt neutron lifetime was calculated for the NBSR, a heavy water-cooled and -moderated research reactor at the National Institute of Standards and Technology. The method is based on the fact that the decay of a pulse of fast neutrons is related to the prompt neutron lifetime (and the multiplication constant for the reactor and the delayed neutron fraction). A Monte Carlo simulation of the decay is then used to calculate the prompt neutron lifetime at two points in the fuel cycle. At the start-up of a new cycle, the prompt neutron lifetime was calculated to be 774 ± 35 s, and at the end of a cycle, it was calculated to be 819 ± 48 s.