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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The last days of Hallam
The Hallam nuclear power plant, about 25 miles southwest of Lincoln, Neb., was an important part of the Atomic Energy Commission’s Reactor Power Demonstration Program. But in the end, it operated for only 6,271 hours and generated about 192.5 million kilowatt-hours of electric power during its short, 15-month life.
Toshihiro Yamamoto, Hiroki Sakamoto
Nuclear Science and Engineering | Volume 198 | Number 8 | August 2024 | Pages 1607-1619
Research Article | doi.org/10.1080/00295639.2023.2266623
Articles are hosted by Taylor and Francis Online.
The inverse reactor period α is a fundamental mode eigenvalue of the α-mode nonlinear Boltzmann eigenvalue equation that considers delayed neutron contributions. Thus far, several Monte Carlo methods, including the α-k, weight balancing, and transition rate matrix methods, have been developed to calculate α. This study presents a new Monte Carlo method for predicting α by using the derivatives of the k-eigenvalue with respect to α. Formulae are derived to calculate the first and second derivatives using the differential operator sampling method. The key feature of the new proposed method is its ability to estimate the uncertainty of the predicted α by considering the uncertainty of the k-eigenvalue and its derivatives with respect to α.