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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
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.
João Moreira, John C. Lee
Nuclear Science and Engineering | Volume 98 | Number 3 | March 1988 | Pages 244-254
Technical Paper | doi.org/10.13182/NSE88-A22325
Articles are hosted by Taylor and Francis Online.
Control rod worth measurements through the inverse kinetics equation depend on accurate determination of the amplitude function from detector signals. The modal-local method introduced in a previous study estimates space-time changes in the flux or shape function so that the amplitude function can be determined accurately and efficiently. A simple thermal-hydraulic feedback model is included in the modal-local method for at-power reactivity analysis. The method is tested with two simulated rod worth measurements: a zero-power rod drop experiment and a differential rod worth measurement in a power reactor. The modal-local method reproduces the reactivity obtained with the FX2-TH time-dependent diffusion theory code with an overall accuracy of 1 to 2%, except for simulated detectors located in the immediate vicinity of the rod motion.