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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Jack Chernick, Russel Vernon
Nuclear Science and Engineering | Volume 4 | Number 5 | November 1958 | Pages 649-672
Technical Paper | doi.org/10.13182/NSE58-A25554
Articles are hosted by Taylor and Francis Online.
Two basic formulas for resonance absorption applicable both to mixtures and to lumps are considered, the narrow resonance (NR) approximation and the infinite mass (NRIA) approximation. The formulas are shown to be complementary, yielding accurate results when the choice between them is based on the practical width of the resonance line as originally suggested by Wigner. The formulas are used to calculate resonance integrals for U238 and Th232. The results yield a low mass absorption term and a surface absorption term proportional to the square root of the surface-to-mass ratio for lumps of practical size in qualitative agreement with the experimental work of Egiazarov and Hellstrand for U238 and with Dayton and Pettus for thorium. Dresner’s suggestion that the ratio of the resonance integral to the mass absorption term is independent of the resonance structure is not borne out. Refinement of the basic formulas is discussed. The correction of the NRIA formula for energy degradation is in agreement with Spinney’s calculations for U-H mixtures and with Monte Carlo results obtained by Auerbach for uranium-water lattices. Consideration of lumping effects indicates that the basic formulas generally underestimate the resonance absorption. It is therefore recommended that the common use of ill-defined flux disadvantage factors be dropped.
