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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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No impact from Savannah River radioactive wasps
The news is abuzz with recent news stories about four radioactive wasp nests found at the Department of Energy’s Savannah River Site in South Carolina. The site has been undergoing cleanup operations since the 1990s related to the production of plutonium and tritium for defense purposes during the Cold War. Cleanup activities are expected to continue into the 2060s.
John M. Carpenter, Yasushi F. Taked, David F. R. Mildner
Nuclear Science and Engineering | Volume 98 | Number 4 | April 1988 | Pages 326-340
Technical Paper | doi.org/10.13182/NSE88-A23533
Articles are hosted by Taylor and Francis Online.
Grooved moderators provide greater neutron leakage currents from their channeled surfaces than flat moderators of the same volume. Operated in conjunction with pulsed sources to provide beams of slow neutrons, their pulse widths depend in a complicated way on the groove parameters, as does the leakage current. A one-speed diffusion theory treatment of the asymmetric grooved moderator is described, the eigenfunctions and eigenvalues are presented, and a simple graphical method for eigenvalue calculation is provided. The leakage from the bottoms of the grooves and from the tips of the fins are separately determined and the lowest order functions for a cold polyethylene moderator are calculated. The results for the lowest order time eigenvalue are in good agreement with a measurement obtained at the Intense Pulsed Neutron Source.