Poyé A, Hulin S, Bailly-Grandvaux M, Dubois J-L, Ribolzi J, Raffestin D, Bardon M, Lubrano-Lavaderci F, D'Humières E, Santos J J, Nicolaï Ph, Tikhonchuk V
Centre Lasers Intenses et Applications, University Bordeaux, CNRS, CEA, Talence 33405, France.
CEA/DAM/CESTA, BP 12, Le Barp 33405, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Apr;91(4):043106. doi: 10.1103/PhysRevE.91.043106. Epub 2015 Apr 22.
In this paper we describe the physical processes that lead to the generation of giant electromagnetic pulses (GEMPs) at powerful laser facilities. Our study is based on experimental measurements of both the charging of a solid target irradiated by an ultra-short, ultra-intense laser and the detection of the electromagnetic emission in the GHz domain. An unambiguous correlation between the neutralization current in the target holder and the electromagnetic emission shows that the source of the GEMP is the remaining positive charge inside the target after the escape of fast electrons accelerated by the ultra-intense laser. A simple model for calculating this charge in the thick target case is presented. From this model and knowing the geometry of the target holder, it becomes possible to estimate the intensity and the dominant frequencies of the GEMP at any facility.
在本文中，我们描述了在强激光装置中导致产生巨型电磁脉冲（GEMPs）的物理过程。我们的研究基于对由超短、超强激光辐照的固体靶的充电以及GHz频段电磁辐射的检测进行的实验测量。靶架中的中和电流与电磁辐射之间明确的相关性表明，GEMP的来源是超强激光加速的快电子逸出后靶内剩余的正电荷。给出了一个用于计算厚靶情况下此电荷的简单模型。根据该模型并了解靶架的几何形状，就有可能估计任何装置中GEMP的强度和主导频率。
