论文部分内容阅读
为了研究强激光与固体靶相互作用产生的电离辐射危害,本文在星光Ⅲ300TW强激光装置上开展了一系列激光打靶实验。实验使用的激光功率密度为5×10~(18)~4×10~(19)W/cm~2,激光脉冲能量为60~153J,靶为直径1mm、厚度1mm的Ta圆柱,本文分别对X射线剂量、X射线能谱和超热电子能谱进行了测量。实验结果表明,测量到的单发最大X射线剂量约为16.8mSv,靠近激光传播方向(0°),距靶50cm处;激光0°方向的X射线剂量随激光功率密度的增加而显著增加,激光90°方向的X射线剂量随激光功率密度的变化相对较小;测量到的X射线能谱可大致用含有两个X射线温度的指数分布函数描述,其中0°方向测量到的X射线温度为0.4~1.15 MeV,90°方向测量到的X射线温度为0.25~0.54 MeV;实测超热电子温度与Wilks定标率符合较好。
In order to study the harm of ionizing radiation caused by the interaction between strong laser and solid target, a series of laser targeting experiments have been carried out on Star III 300TW laser. The experimental laser power density is 5 × 10 ~ (18) ~ 4 × 10 ~ (19) W / cm ~ 2, laser pulse energy is 60 ~ 153J, the target is Ta cylinder with diameter of 1mm and thickness of 1mm. X-ray dose, X-ray energy spectrum and super-heated electron energy spectrum were measured. The experimental results show that the maximum single X-ray dose is about 16.8mSv, near the laser propagation direction (0 °) and 50cm away from the target. The X-ray dose at 0 ° of the laser increases with the increase of laser power density, The X-ray dose at the 90 ° direction of the laser varies relatively with laser power density; the measured X-ray energy spectrum can be roughly described by an exponential distribution function with two X-ray temperatures, where the X-ray temperature measured in the 0 ° direction 0.4 ~ 1.15 MeV. The X-ray temperature measured in 90 ° direction is 0.25 ~ 0.54 MeV. The measured hot electron temperature is in good agreement with Wilks calibration.