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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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).”
D. V. Gopinath, K. Santhanam
Nuclear Science and Engineering | Volume 43 | Number 2 | February 1971 | Pages 197-211
Technical Paper | doi.org/10.13182/NSE71-A21267
Articles are hosted by Taylor and Francis Online.
Here we present the results of extensive calculations on the gamma-ray transport in finite heterogeneous systems using the technique developed in Part I of this paper. Systems studied are water, concrete, aluminum, iron, and lead, and the data presented are: evolution of spectra with collisions, reflected and transmitted spectra, spectra at different depths, and buildup factors for different source energies and different thicknesses of each medium. Similar data are also presented for two-region systems of water-iron, iron-lead, and water-lead. Several interesting results have been observed, among which are: (a) a step structure and a second peak in the low energy part of the back-scattered spectra from light media, (b) progressive buildup of a peak in the low energy region of transmitted flux, and (c) significant dip in the build-up factors near the outer boundary of the systems. The results are discussed on the basis of the physical processes involved. A comparison of the present results with those published in literature is made.