在“强光一号”装置上,利用微型磁探针系统测量了钨丝阵负载内部的消融等离子体携带的电流,对比了有无泡沫柱两种负载条件下内部电流分布的差异,获得了稳定可靠的实验数据.实验中使用了由42根4.2μm钨丝组成的直径12m/n的丝阵负载,脉冲电流峰值为1.34MA,上升时间约70ns.结果表明:在电流放电开始约20ns后,半径3.2inm处的磁探针有明显的信号输出,随后的20ns内,内部等离子体分流比迅速上升至约20%,并在30-40ns内基本保持稳定.丝阵加载泡沫柱后,内部电流值在Z箍缩前期没有明显变化.
The current within imploding multiwire tungsten arrays is measured using micro magnetic probes in the Qiangguang-1 facility at a current of 1.3 MA and rise time of about 70 ns. Difference in current distribution in multiwire arrays between with and without foam cylinder on the array axis is studied. Stable and reliable results are obtained for tungsten wire array Z-pinch with a wire diameter of 4.2 μm and an annular diameter of 12 mm. The results shows that the output of magnetic probe at a radius of 3.2 mm lags about 20 ns behind the discharge current pulse. After that, the ratio of inside current to the total current increases 20% within 20 ns and keeps steady for 30-40 ns. It is found that the foam cylinder has no appreciable influence on the inside current value in the initial stage of implosioin.