激光-薄膜靶相互作用中前向超热电子 的产额及能量转化效率

核聚变与等离子体物理 ›› 2014, Vol. 34 ›› Issue (1): 12-16.

激光-薄膜靶相互作用中前向超热电子的产额及能量转化效率

蔡达锋，谷渝秋，郑志坚，周维民，焦春晔，温天舒

(1. 内江师范学院工程技术学院，内江641112；2. 中国工程物理研究院激光聚变研究中心，绵阳621900)

出版日期:2014-03-15 发布日期:2014-03-14
作者简介:蔡达锋(1963-)，男，四川金堂人，博士，教授，主要研究领域为超短超强激光-等离子体相互作用。
基金资助:
国家自然科学基金资助项目(10975121)和四川省教育厅科研项目(10ZA012)

Yield and energy conversion efficiency of the forward hot electrons from laser-foil target

CAI Da-feng, GU Yu-qiu, ZHENG Zhi-jian , ZHOU Wei-min , JIAO Chun-ye, WEN Tian-shu

(1. School of engineering and technology, Nei Jiang Teachers College, Neijiang 641112; 2. Research Center of Laser Fusion, CAEP, Mianyang 621900)

Online:2014-03-15 Published:2014-03-14

摘要/Abstract

摘要：

采用飞秒激光与薄膜靶相互作用测量了前向超热电子的分布和能谱。结果显示，前向超热电子主要集中在靶背法线方向附近区域发射，而超热电子的能谱呈双温类麦克斯韦分布。根据所测超热电子能谱和分布推算出前向超热电子总产额约1.23×10⁸shot^-1和前向超热电子的总能量约4.65×10¹¹shot^-1，最后给出激光能量转化为前向超热电子能量的转化效率约5.72×10^-4，这些结果与文献[17]的较好地一致。

关键词: 飞秒激光, 薄膜靶, 前向超热电子, 转化效率

Abstract:

The distribution and the energy spectrum of forward hot electrons produced by the interaction of fs-laser with foil target were measured. The results show that the forward hot electrons jet with a large angle width is mainly along the direction of rear normal of target; the energy spectrum of forward hot electrons is a Maxwellian-like distribution. The yield and energy of forward hot electrons is about 1.23×10⁸ shot ^-1 and 4.65×10¹¹ keV . shot ^-1 , which were deduced from the distribution and the energy spectrum of forward hot electrons. The conversion efficiency of laser energy to forward hot electrons energy is about 5.72×10 ^-4 , which is better consistent with that from the reference [17].

Key words: Fs-laser, Foil target, Forward hot electron, Conversion efficiency

中图分类号:

O434.12

蔡达锋，谷渝秋，郑志坚，周维民，焦春晔，温天舒. 激光-薄膜靶相互作用中前向超热电子的产额及能量转化效率[J]. 核聚变与等离子体物理, 2014, 34(1): 12-16.

CAI Da-feng 1, 2 , GU Yu-qiu 2 , ZHENG Zhi-jian 2 , ZHOU Wei-min 2 , JIAO Chun-ye 2 , WEN Tian-shu 2. Yield and energy conversion efficiency of the forward hot electrons from laser-foil target[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2014, 34(1): 12-16.

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