SAWTOOTH ACTIVITY IN OHMICALLY HEATED JET PLASMAS
Detailed studies of sawtooth activity during ohmic plasmas in JET have revealed significant discrepancies both with previously reported observations of the phenonmenon, and with conventional models of the internal disruption. "Compound" sawteeth, which display an intermediate collapse during the ramp phase, are observed in the majority of discharges. These usually exhibit no precursor activity, in contrast to observations in smaller tokamaks, but are often accompanied by successor oscillations. Furthermore, the collapse time of such sawteeth is much faster than expected. These results suggest that the conventional model of the sawtooth is inadequate to explain sawtooth activity in large tokamaks.
Bibliographic Reference: WRITE TO THE PUBLICATIONS OFFICER, JET JOINT UNDERTAKING, ABINGDON, OXON, OX14 3EA (UK), MENTIONING REPORT JET-P(86)05, 1986
Record Number: 1989124111300 / Last updated on: 1987-01-01
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