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Aerospace Nuclear Science & Technology
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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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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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.
K. D. Lathrop
Nuclear Science and Engineering | Volume 119 | Number 1 | January 1995 | Pages 80-86
Technical Notes | doi.org/10.13182/NSE95-A24071
Articles are hosted by Taylor and Francis Online.
The cosine of the laboratory scattering angle is derived for a neutron elastically scattering from a nucleus moving with a specified velocity. Scattering is assumed to be isotropic in the center-of-mass system, and the mean cosine of the laboratory scattering angle is calculated and shown to agree with the first Legendre moment of a scattering probability function derived by Blackshaw and Murray. Isotropic neutron-nucleus encounters are further assumed, and a second average is taken to calculate a mean cosine as a function of the neutron-nuclear speed ratio. This mean cosine approaches 2/(3m), where m is the nucleus mass relative to the neutron mass, as the neutron speed becomes large compared with the speed of the nucleus, but for m > 1, the scattering becomes more anisotropic as this speed ratio decreases before approaching isotropy at small neutron-nucleus speed ratios. This single nuclear speed mean cosine is compared with its average over a Maxwellian distribution of nuclear speeds. The two are qualitatively very similar. Taking the single nuclear speed to be the average speed of the Maxwellian distribution gives better quantitative agreement, in a least-squares sense, between the single-speed mean cosine and the Maxwellian average mean cosine than does using the most probable speed of the Maxwellian distribution.