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Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Dimitri G. Naberejnev, Claude Mounier, Richard Sanchez
Nuclear Science and Engineering | Volume 131 | Number 2 | February 1999 | Pages 222-229
Technical Paper | doi.org/10.13182/NSE99-A2030
Articles are hosted by Taylor and Francis Online.
At this time, experimental transmission data are analyzed with codes like REFIT or SAMMY, which use the free gas model to fit the form of the resonances. The use of the resonance parameters issued from such analysis for further reconstruction of the cross section with codes like NJOY can result in nonnegligible errors in the cross sections as well as in the reaction rates.To analyze the bias introduced on resonance parameters by the use of the free gas model and its consequences on reaction rates, we set up a numerical experiment that closely follows the actual scheme of the nuclear data evaluation.First, we use resonance parameters from the JEF2.2 nuclear library to calculate our reference cross section with Lamb's harmonic crystal model. This cross section is then used to simulate transmission coefficients, and a new set of resonance parameters is obtained using the code REFIT to fit the shape of the transmission with the help of the free gas model. These resonance parameters are used to estimate the errors in the reaction rates.We conclude that the free gas model does not ensure reaction rate conservation. A comparison of the capture rates showed that the discrepancy between this model (with the bias on the resonance parameters described here) and the harmonic crystal model (with initial JEF2.2 parameters) is important for reactor physics. For the first resonance of 238U, which represents 30% of the total 238U absorption in a thermal nuclear reactor, the error in the capture reaction rates reaches 3% for the biased resonance parameters issued from UO2 analysis, and up to 1% for the biased resonance parameters issued from metallic uranium analysis. Such a discrepancy could be corrected using a crystal model for the experimental data analysis.