Incomplete reconnection in sawtooth crashes in ASDEX Upgrade

被引:22
作者
Letsch, A
Zohm, H
Ryter, F
Suttrop, W
Gude, A
Poreelli, F
Angioni, C
Furno, I
机构
[1] Inst Plasmaforsch, D-70569 Stuttgart, Germany
[2] EURATOM, Max Planck Inst Plasmaphys, D-85748 Garching, Germany
[3] MIT, PSFC, Cambridge, MA 02139 USA
[4] Politecn Torino, Ist Nazl Fis Mat, Dept Energet, I-10129 Turin, Italy
[5] Ecole Polytech Fed Lausanne, CRPP, CH-1015 Lausanne, Switzerland
关键词
D O I
10.1088/0029-5515/42/9/302
中图分类号
O35 [流体力学]; O53 [等离子体物理学];
学科分类号
070204 ; 080103 ; 080704 ;
摘要
The temporal evolution of the sawtooth crash in ASDEX Upgrade Ohmic and ECRH heated discharges is analysed using a heuristic reconnection model to simulate measured ECE signals. The method turns out to be well suited to detect islands of width above 0.1-0.2 times the mixing radius; for smaller island widths, we cannot distinguish between the resistive and the ideal mode. Thus, the nature of the precursor oscillation cannot be fully resolved. In contrast, we find that during the crash phase, reconnection is incomplete and a large island persists that fully reconnects on a slower time-scale after the crash. The observations are consistent with a recent sawtooth model.
引用
收藏
页码:1055 / 1059
页数:5
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