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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.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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
Webinar: MC&A and safety in advanced reactors in focus
Towell
Russell
Prasad
The American Nuclear Society’s Nuclear Nonproliferation Policy Division recently hosted a webinar on updating material control and accounting (MC&A) and security regulations for the evolving field of advanced reactors.
Moderator Shikha Prasad (CEO, Srijan LLC) was joined by two presenters, John Russell and Lester Towell, who looked at how regulations that were historically developed for traditional light water reactors will apply to the next generation of nuclear technology and what changes need to be made.
Karl D. Hammond, Francesco Ferroni, Brian D. Wirth
Fusion Science and Technology | Volume 71 | Number 1 | January 2017 | Pages 7-21
Technical Paper | doi.org/10.13182/FST16-110
Articles are hosted by Taylor and Francis Online.
We analyze the effect of subsurface prismatic dislocation loops on the surface morphology and helium clustering behavior of plasma-facing tungsten through the use of molecular dynamics simulations that are moderately large in scale, consisting of approximately 830 000 atoms, and extend to times on the order of 1 μs. This approach eliminates some finite-size effects common in smaller simulations and reduces the flux to~5.5 × 1026 m−2 s−1, including ions that reflect back into the plasma—this flux is a factor of ~15 lower than is typically used in smaller simulations. These results indicate that prismatic loops with radii of ~3 nm that are centered 10 nm below the surface with Burgers vectors parallel to the surface cause helium atom clusters to accumulate at the edge of the dislocation core relatively quickly—within 100 to 150 ns of the onset of plasma exposure. Subsequent growth of these clusters, however, is relatively minimal even out to 1 μs or more. This is partially explained by the relatively high helium implantation flux, which causes bubbles to accumulate 0 to 7 nm below the surface and block the region of the metal containing the dislocation, but this is only part of the explanation. Another effect results from the strain field around the loop itself. The compressive regions along the direction of the Burgers vector repel helium, but the tensile region initially attracts helium and traps it. However, we believe that the attractive tensile stress region is effectively shielded by the formation of helium clusters on and above it, and these bubbles subsequently experience relatively slow growth.