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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).”
Glen A. Mortensen and Harold P. Smith, Jr.
Nuclear Science and Engineering | Volume 22 | Number 3 | July 1965 | Pages 321-327
Technical Paper | doi.org/10.13182/NSE65-A20936
Articles are hosted by Taylor and Francis Online.
The time dependent P1 approximation to the neutron transport equation has been solved for the case of an oscillating source on one face of a finite parallelepiped. An oscillatory solution to the differential equations describes the propagation of neutron waves through the medium. Attenuation lengths of plane neutron waves were identical at low frequencies (ω < ½ νΣa) for the P1 and diffusion approximations but differ considerably at high frequencies (ω > 2ν Σtr). Wave lengths and wave speeds for the two approximations were slightly different at low frequencies, identical at immediate frequencies and considerably different at high frequencies. A new method, which considers the transient behavior of a spatially-integrated positive-definite function of flux and current, is used to show that the transient part of the solution decays to zero.