Abstract

We carry out a numerical modeling of plasma injection with hot electrons into a thin layer of cold plasma in the presence of an external magnetic field. We show that the latter can significantly affect the emerging small-scale current filaments and sheets, even if it does not magnetize the particles and does not change the overall dynamics of the redistribution of the total plasma density in the process of injection. The effect observed depends on the orientation of the external magnetic field that is parallel to the plane that bounds the cold plasma layer, if the injection occurs from a narrow strip lying in this plane. In this situation, which corresponds to the ablation of a flat target by a femtosecond laser beam using cylindrical focusing, we study the evolution of the characteristic structures of the formed small-scale magnetic field. It is established that its generation is associated with instabilities of the anisotropic velocity distribution of electrons and that its value can be many times greater than the value of the external magnetic field.

中文翻译：

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均匀磁场对将热电子等离子体注入不均匀冷等离子体层期间产生强小尺度磁场的影响

摘要

我们对在存在外部磁场的情况下将热电子注入冷等离子体薄层的等离子体进行了数值模拟。我们表明，后者可以显着影响新兴的小规模电流丝和片，即使它不会磁化粒子并且不会改变注入过程中总等离子体密度重新分布的整体动力学。如果注入是从位于该平面上的窄带发生的，则观察到的效应取决于与冷等离子体层边界平面平行的外部磁场的方向。在这种情况下，对应于使用柱面聚焦的飞秒激光束烧蚀平面目标，我们研究了所形成的小尺度磁场的特征结构的演变。已确定其产生与电子各向异性速度分布的不稳定性有关，并且其值可能比外部磁场的值大许多倍。