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TJ-II:Instabilities: Difference between revisions
→ELM-like modes
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ELM-like activity has been observed in plasmas with a stored energy above 1 kJ. The plasma is observed to develop bursts of magnetic activity (seen in Mirnov coil signals) which are followed by a large and distinct spike in the H<sub>α</sub> signal. An increase in electrostatic and magnetic fluctuations at the plasma edge and a cold pulse towards the plasma centre are also characteristic of these events. In addition, the electron temperature profile locally flattens at the plasma radius where the temperature is in the range 100-200 eV. This flattening can be explained in terms of enhanced electron heat conductivity. Between ELM-like events the electromagnetic turbulence at the edge decreases and the Te profiles recover their former shapes. This activity is probably triggered by a resonant m = 2, n = 3 mode. | ELM-like activity has been observed in plasmas with a stored energy above 1 kJ. The plasma is observed to develop bursts of magnetic activity (seen in Mirnov coil signals) which are followed by a large and distinct spike in the H<sub>α</sub> signal. An increase in electrostatic and magnetic fluctuations at the plasma edge and a cold pulse towards the plasma centre are also characteristic of these events. In addition, the electron temperature profile locally flattens at the plasma radius where the temperature is in the range 100-200 eV. This flattening can be explained in terms of enhanced electron heat conductivity. Between ELM-like events the electromagnetic turbulence at the edge decreases and the Te profiles recover their former shapes. This activity is probably triggered by a resonant m = 2, n = 3 mode. | ||
<ref>[http://dx.doi.org/10.1088/0029-5515/40/11/306 I. García-Cortés et al, Nucl. Fusion '''40''' (2000) 1867-1874]</ref> | <ref>[http://dx.doi.org/10.1088/0029-5515/40/11/306 I. García-Cortés et al, Nucl. Fusion '''40''' (2000) 1867-1874]</ref> | ||
<ref>[http://dx.doi.org/10.1088/0741-3335/48/5/002 J.A. Jiménez et al, Plasma Phys. Control. Fusion '''48''' (2006) 515-526]</ref> | |||
== References == | == References == | ||
<references /> | <references /> | ||