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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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Latest News
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.
J. Valko, P. V. Tsvetkov, J. E. Hoogenboom
Nuclear Science and Engineering | Volume 135 | Number 3 | July 2000 | Pages 304-307
Technical Note | doi.org/10.13182/NSE00-A2143
Articles are hosted by Taylor and Francis Online.
The double heterogeneity of the core of pebble bed-type high-temperature reactors (HTRs) requires special attention when lattice codes are applied to a unit cell of such systems. As the self-shielding of the resonance absorption takes place in the small fuel grains in the pebbles, the grain-lattice calculation should apply a Dancoff factor for the grain lattice yet take into account the finiteness of the grain lattice in a pebble and the possibility of a neutron reaching another pebble. In a study of HTR lattices, the Dancoff factor was calculated using the DANCOFF-MC program. For a finite lattice of fuel grains in the fuel region of a pebble, the space-dependent Dancoff factor was calculated, and it was averaged over the volume of the fuel in one pebble. This single-pebble Dancoff factor was further corrected to include the effect of other pebbles. The sensitivity of the Dancoff factor to core composition and the sensitivity of core calculations to the Dancoff factor are discussed, and a numerical example is given.