Enhancing the number of high-energy electrons deposited to a compressed pellet via double cones in fast ignition.
Enhancing the number of high-energy electrons deposited to a compressed pellet via double cones in fast ignition.
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DOI：
10.1103/physrevlett.102.245001
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发表时间：
2009-06
影响因子：
8.6
通讯作者：
H. Cai;K. Mima;Weimin Zhou;T. Jozaki;H. Nagatomo;A. Sunahara;R. Mason
中科院分区：
文献类型：
--
作者：
H. Cai;K. Mima;Weimin Zhou;T. Jozaki;H. Nagatomo;A. Sunahara;R. Mason
采用粒子模拟的方法，研究了双锥结构对提高入射激光能量与压缩核耦合效率的影响。结果表明，双锥翼内的真空间隙大大减少了从锥侧逸出的高能电子数。发现了两种限制高能电子的主要机制，即内锥翼后部的鞘层电场和真空间隙内的准静态磁场。详细讨论了准静态磁场的产生机制。结果发现，准静态场继续限制的高能电子超过几皮秒。双锥提供约15%的输入能量的限制和聚焦，用于在压缩芯中沉积。
Particle-in-cell simulations aimed at improving the coupling efficiency of input laser energy deposited to a compressed core by using a double cone are described. It is found that the number of high-energy electrons escaping from the sides of the cone is greatly reduced by the vacuum gap inside the wing of the double cone. Two main mechanisms to confine high-energy electrons are found. These mechanisms are the sheath electric field at the rear of the inner cone wing and the quasistatic magnetic field inside the vacuum gap. The generation mechanism for the quasistatic magnetic fields is discussed in detail. It is found that the quasistatic fields continue to confine the high-energy electrons for longer than a few picoseconds. The double cones provide confinement and focusing of about 15% of the input energy for deposition in the compressed core.