为研究毛细管放电X光激光中预脉冲放电对增益的影响,用简化的XDCH程序,模拟计算了聚乙烯毛细管充Ar气、2μs脉宽的预脉冲放电过程,把预放电之后的等离子体温度、密度和电离度作为初始条件,输入XDCH程序,进行40kA典型主脉冲放电的计算模拟,给出了一些典型预放电幅度下的增益和电子密度分布情况.比较分析的结果发现,对2μs脉宽的预脉冲,100A的电流将得到较好的增益,并且预言激光线时间谱可能出现双峰结构,空间谱会出现环状结构.

In order to study the influence by pre-pulse discharge on capillary discharge pumped X-ray Laser, in this paper, a simplified XDCH code is used to simulate the process of pre-discharge with 2μs pulse width in polythene capillary filled with Ar. The plasma temperature, density and ionization degree calculated as initial condition are inputted into XDCH code to simulate typical main-discharge with 40kA. From the view of 1-dimension, some gain coefficient and electron density distributions with typical pre-pulse amplitudes are given. After analysis and comparison, conclusion is drawn that 100A pre-pulse with 2μs width can lead to higher gain. Two-peak structure in time spectrum and ring-like structure in space spectrum of 46.9nm laser line are predicted.