HT-7装置上充气对低杂波耦合影响的实验及分析

Experiments and Analysis of Effect of Gas Injection During Coupling of Lower Hybrid Waves in HT-7

摘要: 在低杂波（LHW）天线端口充D₂和CD₄，发现LHW的耦合效果能得到明显改善，充气后LHW的反射系数基本降为6%左右。不同窗口充气对波的耦合和等离子体密度的影响不同，其原因是改善耦合的关键是提高刮削层（SOL）内等离子体的密度。D₂与CH₄对LHW耦合影响的实验结果表明：D₂对LHW的耦合效果影响略好于CH₄，但D₂对等离子体密度的影响明显高于CH₄，原因是D₂对电子密度的贡献更大。

Abstract: Good coupling of lower hybrid waves （LHW）was viewed during the gas （D₂ and CD₄） injection around the antenna, and the reflection coefficient of LHW was mostly decreased to 6%. The effects of LHW coupling and density are not the same when gas is injected in different pipes, because the key factor for the good coupling is the increase of local density in the scrape-off layer (SOL). The comparison between effects of D₂ and CH₄ on wave-plasma coupling shows coupling is a little better with D₂ puffing and D₂ gives higher electron density in the SOL than CH₄. This is becauseD₂ makes a greater contribution to the increase of density.