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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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. Venkataraman, R. F. Fleming, E. D. McGarry
Nuclear Science and Engineering | Volume 126 | Number 3 | July 1997 | Pages 314-323
Technical Paper | doi.org/10.13182/NSE97-A24483
Articles are hosted by Taylor and Francis Online.
A new measurement-based method has been developed to determine the photofission contribution to measured responses of fission reactions in a mixed radiation field of neutrons and photons. Using this method, reliable upper and lower bounds can be established for the photofission contributions. Knowledge of the photon energy spectrum and the photofission cross sections is not required. The method involves the measurement and calculation of spectral indices of a fission reaction relative to a reaction whose response does not include any photon contribution. The differential changes in the spectral indices are measured as well as calculated with and without a gamma-ray attenuator. The measurements include responses from both neutrons and photons, whereas the calculations include contributions from neutrons only. An equation is derived for the ratio of photofission rate to neutron-induced fission rate using the definitions of the spectral indices. From this equation, algebraic upper and lower bounds can be determined for the photofission contribution using a minimum and a maximum value for the mass attenuation coefficient of the gamma-attenuating material at all photon energies. The method was tested in the radiation field inside the Materials Dosimetry Reference Facility (MDRF), which is a National Institute of Standards and Technology reference neutron field operating at the Ford Nuclear Reactor at the University of Michigan. Established algebraic upper bounds for the photofission contributions to the 237Np and 238U fission reactions in the MDRF were found to overlap zero. Conservative statistical upper bounds were established at the la level of confidence, and these are 0.87% for the 237Np fission reaction and 0.55 % for the 238U fission reaction.
