Effects of resistive magnetic field on fast electron divergence measured in experiments
Effects of resistive magnetic field on fast electron divergence measured in experiments
复制标题
DOI：
10.1088/0741-3335/57/2/025011
复制
发表时间：
2015-02
影响因子：
2.2
通讯作者：
X. Yang;H. Zhuo;Y. Ma;H. Xu;T. Yu;D. Zou;Z. Ge;B. B. Xu-B.;Q. Zhu;F. Shao;M. Borghes
中科院分区：
文献类型：
--
作者：
X. Yang;H. Zhuo;Y. Ma;H. Xu;T. Yu;D. Zou;Z. Ge;B. B. Xu-B.;Q. Zhu;F. Shao;M. Borghes
通过细胞内粒子模拟研究了超强激光驱动的快速电子通过埋在固体靶中的示踪层的传输。研究发现，由于目标层和示踪层之间的电阻率梯度陡峭，材料界面处会产生数千特斯拉的强电阻磁场。这样的磁场可以显着抑制电子的快速传播。能够穿透第一界面的电子大部分被磁场限制在埋层中并引起示踪层的加热。加热区域的横向范围可以明显大于相对论电子束的横向范围。这一发现表明，实验中从 Kα X 射线发射推断出的相对论电子发散度可能被高估了。
Transport of fast electrons driven by an ultraintense laser through a tracer layer buried in solid targets is studied by particle-in-cell simulations. It is found that intense resistive magnetic fields, having a magnitude of several thousand Tesla, are generated at the interfaces of the materials due to the steep resistivity gradient between the target and tracer layer. Such magnetic fields can significantly inhibit the fast electron propagation. The electrons that can penetrate the first interface are mostly confined in the buried layer by the magnetic fields and cause heating of the tracer layer. The lateral extent of the heated region can be significantly larger than that of the relativistic electron beam. This finding suggests that the relativistic electron divergence inferred from Kα x-ray emission in experiments might be overestimated.