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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).”
Jesson D. Hutchinson, John D. Bess
Nuclear Science and Engineering | Volume 163 | Number 3 | November 2009 | Pages 285-290
Technical Paper | doi.org/10.13182/NSE163-285
Articles are hosted by Taylor and Francis Online.
Subcritical measurements were conducted with an -phase plutonium sphere reflected by nickel hemishells using the 252Cf source-driven noise analysis method to provide criticality safety benchmark data. Measured configurations included a bare plutonium sphere as well as the plutonium sphere reflected by the following nickel thicknesses: 1.27, 2.54, 3.81, 5.08, and 7.62 cm. A certain ratio of spectral quantities was measured for each configuration, which varies linearly with the keff of the system under small perturbations. In addition, two types of Monte Carlo calculations were employed: a modified version of MCNP to calculate the ratio of spectral quantities and a KCODE calculation. From the measured and computed quantities, the effective multiplication factor of each configuration can be approximated. The inferred keff for all six configurations compared well with computed values. A comprehensive uncertainty analysis was then performed that includes uncertainties in the geometry and materials present in the system in addition to the uncertainties in the method and nuclear data.