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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Latest News
Joint NEA project performs high-burnup test
An article in the OECD Nuclear Energy Agency’s July news bulletin noted that a first test has been completed for the High Burnup Experiments in Reactivity Initiated Accident (HERA) project. The project aim is to understand the performance of light water reactor fuel at high burnup under reactivity-initiated accidents (RIA).
Thomas E. Booth
Nuclear Science and Engineering | Volume 148 | Number 3 | November 2004 | Pages 391-402
Technical Paper | doi.org/10.13182/NSE04-A2465
Articles are hosted by Taylor and Francis Online.
The variance in Monte Carlo particle transport calculations is often dominated by a few particles whose importance increases manyfold on a single transport step. This paper describes a novel variance reduction method that uses a large importance change as a trigger to resample the offending transport step. That is, the method is employed only after (ex post facto) a random walk attempts a transport step that would otherwise introduce a large variance in the calculation.Improvements in two Monte Carlo transport calculations are demonstrated empirically using an ex post facto method. First, the method is shown to reduce the variance in a penetration problem with a cross-section window. Second, the method empirically appears to modify a point detector estimator from an infinite variance estimator to a finite variance estimator.