纳秒、飞秒激光脉冲下铝等离子体发射光谱及其空间特性的比较

Comparison of Characteristics of X-Ray Emission And Its Spatial Distributions in an Alumium Plasma Using fs and ns Laser Pulses

研究了４５ ｆｓ和６ ｎｓ的强激光脉冲作用铝靶等离子体的发射光谱特性，发现在飞秒下Ｘ射线发射以Ｋ 壳层为主，等离子体的温度（５００ ｅＶ），电子密度（３×１０２１／ｃｍ ３）比纳秒情况（１００ ｅＶ，２×１０２０／ｃｍ ３）下要高；铝等离子体的Ｘ射线发射长度短而且强区更靠近靶面。

The characteristics of X ray emission in aluminum plasmas using 45 fs and 6 ns pulsed lasers respectively are reported. It shows that under the fs laser, the X ray emission is dominantly from the K shell, the aluminum plasma′s temperature is 500 eV and the electron density is 3×10 21 /cm 3, while under the ns laser, the L shell, 100eV and 2×10 20 /cm 3 are obtained correspondingly. The spatial distributions are also compared simply.