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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.
Douglas J. Rzepecki
Nuclear Technology | Volume 69 | Number 3 | June 1985 | Pages 279-292
Technical Paper | Nuclear Safety | doi.org/10.13182/NT85-A33611
Articles are hosted by Taylor and Francis Online.
The time-dependent radiation transport for a demonstration scale liquid-metal-cooled fast breeder reactor that has undergone a severe loss of sodium coolant is calculated with both a discrete ordinates and a diffusion theory solution for the real neutron flux shape. It is found that diffusion theory underpredicts reactivity levels by about $6 when compared to discrete ordinates. It is also found that the use of an initial adjoint neutron flux throughout the transient as a reactivity weighting function could seriously underpredict reactivity levels for a severely degraded reactor core. In both cases, there was an immediate termination of the excursion. The uncertainty of being limited to two fuel fields for an end of equilibrium cycle reactor core in SIMMER-II during the transient was greater than that due to microscopic cross-section shielding factor iteration and interpolation schemes. Fifty-energy-group reactivity coefficients were best duplicated in collapsing to a ten-energy-group set with an entire reactor integrated bilinear neutron energy flux spectrum.