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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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August 2025
Latest News
IAEA program uses radioisotopes to protect rhinos
After two years of testing, the International Atomic Energy Agency and the University of the Witwatersrand in Johannesburg, South Africa, have begun officially implementing the Rhisotope Project, an innovative effort to combat rhino poaching and trafficking by leveraging nuclear technology.
Xian-Zhu Tang, Zehua Guo
Fusion Science and Technology | Volume 71 | Number 1 | January 2017 | Pages 110-121
Technical Note | doi.org/10.13182/FST16-119
Articles are hosted by Taylor and Francis Online.
With a divertor made of solid materials like carbon and tungsten, plasma ions are expected to be recycled at the divertor surface with a time-averaged particle recycling coefficient very close to unity in steady-state operation. This means that almost every plasma ion (hydrogen and helium) will be returned to the plasma, mostly as neutrals. The power flux deposited by the plasma on the divertor surface, on the other hand, can have varying recycling characteristics depending on the material choice of the divertor; the run-time atomic composition of the surface, which can be modified by material mix due to impurity migration in the chamber; and the surface morphology change over time. In general, a high-Z–material (such as tungsten) surface tends to reflect light ions and produce stronger power recycling, while a low-Z–material (such as carbon) surface tends to have a larger sticking coefficient for light ions and hence lower power recycling. Here, an explicit constraint on target plasma density and temperature is derived from the truncated bi-Maxwellian sheath model, in relation to the absorbed power load and power recycling coefficient at the divertor surface. It is shown that because of the surface recombination energy flux, the attached plasma has a sharper response to power recycling in comparison to a detached plasma.