Transition from no-ELM response to pellet ELM triggering during pedestal build-up—insights from extended MHD simulations

  title={Transition from no-ELM response to pellet ELM triggering during pedestal build-up—insights from extended MHD simulations},
  author={Shimpei Futatani and A. Cathey and Matthias Hoelzl and P T Lang and Gta Guido Huijsmans and M. Dunne and the JOREK team and the ASDEX Upgrade team and the EUROfusion MST1 team},
  journal={Nuclear Fusion},
Pellet edge localized mode (ELM) triggering is a well-established scheme for decreasing the time between two successive ELM crashes below its natural value. Reliable ELM pacing has been demonstrated experimentally in several devices, increasing the ELM frequency considerably. However, it was also shown that the frequency cannot be increased arbitrarily due to a so-called lag-time. During this time, after a preceding natural or triggered ELM crash, neither a natural ELM crash occurs nor is it… 
Comparing spontaneous and pellet-triggered ELMs via non-linear extended MHD simulations
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Investigations on the ELM cycle by local 3D perturbation experiments
An experimental study is performed to investigate the underlying physics of ELM triggering by imposing local perturbations at the plasma edge. Deuterium is injected during type-I ELMy H-mode phases
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A triggering mechanism responsible for the explosive onset of edge localised modes (ELMs) in fusion plasmas is identified by performing, for the first time, non-linear magnetohydrodynamic simulations
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ELM frequency control by continuous small pellet injection in ASDEX upgrade
Injection of cryogenic deuterium pellets has been successfully applied in ASDEX Upgrade for external edge localized mode (ELM) frequency control in type-I ELMy H-mode discharge scenarios. A pellet