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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.
Won S. Park, Yong H. Kim, Chang K. Park, Jong S. Chung, Chang H. Kim
Nuclear Science and Engineering | Volume 143 | Number 2 | February 2003 | Pages 188-201
Technical Paper | doi.org/10.13182/NSE03-A2329
Articles are hosted by Taylor and Francis Online.
A design study for the fission product (FP) target was performed to maximize the transmutation of 99Tc and 129I in the Hybrid Power Extraction Reactor (HYPER) system without causing any core safety concerns. Localized thermal flux is obtained by inserting moderators such as CaH2. Many types of target design concepts have been investigated. The concept where 99Tc is loaded as a plate type in the outermost region and 129I is loaded as NaI rods mixed with CaH2 rods in the inner region is concluded to be the most effective in terms of transmutation rate and core power peaking. The proposed FP target is estimated to have a net transmutation rate of 5.53%/effective full-power year (EFPY) and 11.41%/EFPY for 99Tc and 129I, respectively, which are much higher compared to the transmutation rates in other fast neutron systems. In addition, the support ratios of the HYPER system for 99Tc and 129I are 5.7 and 4.0, respectively, very similar to the support ratio of TRU. The maximum pin power peaking with the loading of the FP target is 1.232, which is within the acceptable range. The loading of the FP target increases the inventory of TRU and makes the core coolant void coefficient more negative but the Doppler coefficient less negative. The proposed FP target configuration causes no safety problems in terms of core neutronics.
