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November 9–12, 2025
Washington, DC|Washington Hilton
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A wave of new U.S.-U.K. deals ahead of Trump’s state visit
President Trump will arrive in the United Kingdom this week for a state visit that promises to include the usual pomp and ceremony alongside the signing of a landmark new agreement on U.S.-U.K. nuclear collaboration.
Howard Wilson
Fusion Science and Technology | Volume 57 | Number 2 | February 2010 | Pages 174-182
Equilibrium and Instabilities | Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics | doi.org/10.13182/FST10-A9408
Articles are hosted by Taylor and Francis Online.
As one increases the heating power in a tokamak beyond a threshold, the confinement undergoes a bifurcation, with a dramatic increase in the confinement time by a factor ~2. This improved confinement regime, or H-mode, is primarily due to the formation of an insulating region at the plasma edge, where steep pressure gradients can form. A feature of H-mode operation is a series of explosive plasma events, called Edge Localised Modes, or ELMs. They repeatedly expel large amounts of energy and particles from the plasma, with serious consequences for the heat loads that plasma facing components must be designed to handle. The present understanding of these ELMs in terms of ideal magneto-hydrodynamic instabilities will be reviewed in this paper.