ABSTRACT

The effects of the atomic number of the fill gas on hard x-ray and ion beam emission from a 2.2 kJ plasma focus were studied. Hydrogen, Nitrogen and Argon gases were used in the experiment. The anode voltage and discharge current were measured to calculate plasma inductance and to study the pinching regime in the three gases. The results showed that the heavier gas in the machine increases the duration of x-ray radiation, ion beam emission, and results in larger pinching plasma inductance. The Lee model suggests that the increase in the pinching plasma inductance can be explained by the occurrence of radiation collapse in the pinch operated with Argon gas. It is postulated that the occurrence of anomalous plasma heating may stop plasma compression and prevent the plasma from a complete collapse to reach near-zero radius.

摘要

研究了填充气体原子序数对2.2 kJ等离子体焦点产生的硬X射线和离子束发射的影响。实验中使用了氢气，氮气和氩气。测量阳极电压和放电电流以计算等离子体电感并研究三种气体中的收缩状态。结果表明，机器中较重的气体会增加X射线辐射的持续时间，离子束发射，并导致更大的收缩等离子体电感。Lee模型表明，夹挤等离子体电感的增加可以用在用氩气操作的夹挤中发生辐射塌陷来解释。据推测，异常等离子体加热的发生可停止等离子体压缩并防止等离子体完全塌陷以达到接近零的半径。