Formation and stability of electromagnetic volticies in high-beta plasmas

(1)新型微片式磁探针的研制为了在高密度等离子体中探测精确的磁结构，我们研制了一种新型的微片式电感微磁探针。这些芯片通过振荡磁场校准，并显示出良好的重现性。(2)用螺旋天线激发Alfven波一种由环形线圈和Rogowski线圈组成的螺旋天线，用来激发压缩和剪切Alfven波，我们研究了用环形线圈和Rogowski线圈电流的组合来激发大振幅m=0的剪切Alfven波。在含有分界线结构的磁场位形中激发了m=0的剪切阿尔芬波。发现波的振幅在分界线内部增加。利用多通道微磁探针阵列测量了微区的空间分布和时间演化。

(1) Development of new micro-chip magnetic probesIn order to detect a precise magnetic structure in a high density plasma, we have developed a new micro-magnetic-probe using a integrated micro-chip inductor. These chips were calibrated by oscillating magnetic field and showed a good reproducibility.(2) Excitation of Alfven waves by a helicity antennaA helicity antenna, which consisted of a loop coil and Rogowski coil, was newly developed to excite a compressional and shear Alfven waves.We have examined to excite a large amplitude m=0 shear Alfven wave by a combination of the loop and Rogowski coil currents. A m=0 shear Alfven wave was excited in a magnetic field configuration including a separatrix structure. It was found that the amplitude of the waves increased inside of the separatrix. Spatial profiles and temporal evolutions were measured by a multi-channel micro magnetic probe array.