Correlations of ELM frequency with pedestal plasma character- istics
نویسندگان
چکیده
Theoretical study of ELMs as a relaxation phenomenon has been performed. It is motivated by the balance between plasma heating and the loss of energy during ELM turbulences. The energy balance is examined for particular heating scheme with neutral beam injection (NBI) in steady state scenarios of ASDEX Upgrade, JET, DIII-D and JT-60U with ELM oscillations. In this approach we have calculated the relaxation time in the pedestal region for corresponding plasma temperature and density. Apparent correlation is found between ELM frequencies and the relaxation time in the pedestal region. This correlation reveals a crucial role of pedestal properties in ELM triggering. It allows to derive predictions for the behaviour of ELMs in conditions of future experiments with ITER.
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Correlations of Elm Frequency with Pedestal Plasma Properties
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