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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.
R. J. Gehrke, J. I. Anderson*, D. H. Meikrantz
Nuclear Technology | Volume 49 | Number 1 | June 1980 | Pages 165-173
Technical Paper | Nuclear Power Reactor Safety / Analysis | doi.org/10.13182/NT80-A32518
Articles are hosted by Taylor and Francis Online.
A technique for measuring the efficiency of a Ge(Li) spectrometer for gamma-ray sources in “gas bomb” geometries has been developed. The compounds of (CH3)2Se, CH3CH2Br, and CH3I are labeled with 75Se, 82Br, and 131I, respectively. These compounds readily vaporize at reduced pressure. The labeled compounds are flame sealed in small ampoules and the gamma-ray emission rates are measured. The contents of each ampoule are then released into the evacuated gas bomb and the efficiency of the detector for the gas bomb geometry is determined from the emitted gamma rays. The radionuclides of 75Se, 82Br, and 131I emit gamma rays that cover the energy range from 66 to ∼1900 keV without any large gaps. A method is suggested for measuring the efficiency for gas bomb geometries at small detector distances, which minimizes the effect of coincidence summing.
