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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
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
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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ANS designates Armour Research Foundation Reactor as Nuclear Historic Landmark
The American Nuclear Society presented the Illinois Institute of Technology with a plaque last week to officially designate the Armour Research Foundation Reactor a Nuclear Historic Landmark, following the Society’s decision to confer the status onto the reactor in September 2024.
E. Starr, H. Honeck, J. DeVilliers†
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 230-235
Technical Paper | doi.org/10.13182/NSE64-A18322
Articles are hosted by Taylor and Francis Online.
This describes an experimental technique to determine the average velocity of the thermal-neutron spectrum as a function of time in a pulsed-neutron experiment. The measurement of the average velocity as a function of time is used to determine two parameters: the time necessary to establish an asymptotic spectrum, and the average velocity of the asymptotic spectrum. The variation in the asymptotic average velocity with material buckling is described by a “spectral-shift coefficient” which is related to the diffusion-cooling coefficient. It was found necessary to wait 2 milliseconds for the establishment of an equilibrium spectrum in graphite, and 0.6 milliseconds in heavy water, and that these values are insensitive to the geometric buckling. Values of the spectral-shift coefficient are given and compared with theoretical estimates.
