利用侧向阴影照相技术探测靶的飞行速度

 建立起一套侧向阴影照相的光学系统,利用可见光作为探测光,在状态方程实验中对靶的飞行速度进行探测。在天光KrF准分子激光装置上进行激光打靶实验,激光波长为248.4 nm。在激光功率密度为8.3×10¹¹ W/cm²的条件下,测得50 μm厚铝靶的飞行速度为3.28 km/s;在激光功率密度为4.7×1010¹¹ W/cm²的条件下,测得带100 μm厚烧蚀层的13 μm厚铝靶的飞行速度为2.52 km/s。最后进行了误差分析计算,实验中探测激光与靶表面偏离角度最大不会超过2.06°,偏离角对实验精度产生的影响可以被忽略。

Detection of flyer velocity by side-on shadowgraph system in equation of state experiment

A side-on shadowgraph system was developed to dectect the velocity of the target in the equation of state experiments, using the visible laser as detection beam. The equation of state experiments were carried out on the high power excimer laser system called “HeavenⅠ” with laser wavelength of 248.5 nm. The velocity of 50 μm thick aluminum target was 3.28 km/s with laser intensity of 8.3×1011 W/cm2, and the velocity of 13 μm thick aluminum target with 100 μm thick ablator was 2.52 km/s with laser intensity of 4.7×1011 W/cm2. Through analysing the error between the experiment and the caculation, the maximum angle between detection beam and target was 2.06°, and the error cased by such an angle could be neglected for the accuracy of the experiments.