强激光辐照平面靶与柱腔靶产生电磁脉冲对比研究

Comparative Investigation of Electromagnetic Pulses Generated by Strong Laser Irradiating Planar and Hohlraum Targets

通过脉冲接收天线的设计和测试方法的优化,建立了神光Ⅲ原型激光器电磁脉冲(EMP)的强度分布等激光参数和靶型的关系,为进一步研究它们的产生机理和激光靶相互作用提供实验依据。考虑到电磁场极化方向的不确定性,使用三个相互正交的环形磁天线对激光装置靶室内部的电磁脉冲信号进行了测量,对比分析了两种靶型辐射电磁脉冲信号的频域特性,探讨了天线摆放位置对信号强度的影响,同时通过多物理场模拟对球形腔内电磁场的分布进行了分析。

By designing pulsed receiving antennas and optimizing test methods, the relationship between laser parameters, such as intensity distribution of electromagnetic pulses （EMPs） from SGIII prototype laser facility and target type is established, which can provide an experimental basis for further investigating EMP generation mechanism and laser target interaction. Based on the consideration of the polarization direction uncertainty of electromagnetic fields, three mutual orthogonal magnetic loop antennas are selected to measure the EMP signal inside the target chamber of the laser facility. A comparative analysis on the frequency features of the EMP signals from two kinds of targets is conducted, and the influence of antenna position on the signal strength is discussed. At the same time, the distribution of EMPs inside the spherical chamber is analyzed by multi-physics simulation.