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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
Standards Program
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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High temperature fission chambers engineered for AMR/SMR safety and performance
As the global energy landscape shifts towards safer, smaller, and more flexible nuclear power, Small Modular Reactors (SMRs) and Gen. IV* technologies are at the forefront of innovation. These advanced designs pose new challenges in size, efficiency, and operating environment that traditional instrumentation and control solutions aren’t always designed to handle.
Robert W. Albrecht
Nuclear Science and Engineering | Volume 14 | Number 2 | October 1962 | Pages 153-158
Technical Paper | doi.org/10.13182/NSE62-A28114
Articles are hosted by Taylor and Francis Online.
A mathematical model is developed for the ratio of the variance to the mean number of neutrons detected in a point, unloaded reactor as a function of counting time. The model includes the effect of delayed neutrons. An experiment is performed which measures this statistic for counting times between one millisecond and ten seconds. The predictions of the model and the results of the experiment are compared. It is shown that a reduced two-delay group model predicts the experimental results fairly well.