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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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Friedbert Kappler
Nuclear Technology | Volume 27 | Number 2 | October 1975 | Pages 224-232
Technical Paper | Reactor | doi.org/10.13182/NT75-A24289
Articles are hosted by Taylor and Francis Online.
The problem of strong space-dependent neutron spectra appearing at boundaries is studied at a sodium-iron interface in slab geometry. The spatial neutron spectra from a 14-MeV neutron source were measured in the energy range from 100 eV to 4.5 MeV. For the energy E < 200 keV, the time-of-flight method was employed and for E > 200 keV, proton-recoil detectors were used. In addition, calculations were performed with the Karlsruhe transport codes DTK and SNOW. The comparison of measured and calculated spectra, both functions of space and energy, showed that the spectrum around the sodium resonance is well described by 208 energy groups. A relationship is developed that is a function of the resonance parameters and the properties of the material concerned, from which it is possible to estimate the depth to which the flux depression at a resonance energy propagates into an adjacent material.
