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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
A. Travelli, Gerald P. Calame
Nuclear Science and Engineering | Volume 20 | Number 4 | December 1964 | Pages 414-427
Technical Paper | doi.org/10.13182/NSE64-A20983
Articles are hosted by Taylor and Francis Online.
The thermal neutron space-time eigenvalue spectrum of the multigroup PN approximation is investigated numerically for a modified form of the Radkowsky Kernel. Both discrete eigenvalues and eigenvalues that are assigned to a ‘continuum region,’ on the grounds that the corresponding eigenvectors exhibit singularities, are found. The continuum region so defined agrees well with that expected for the Boltzmann Equation. It is found that, when λ, the time decay constant, is plotted vs B2, the square of the geometrical buckling, there is in the PN approximation a critical value beyond which no real eigenvalues λ exist. The value of is sensitive to the order of the PN approximation, increasing with increasing N. It is conjectured that corresponds, when the extrapolated endpoint is considered, to a slab of zero thickness through which a burst of neutrons would pass undisturbed as an ideal travelling wave.