飞秒激光与Cu靶和CH靶相互作用产生的快电子能谱实验研究

核聚变与等离子体物理 ›› 2014, Vol. 34 ›› Issue (4): 307-313.

飞秒激光与Cu靶和CH靶相互作用产生的快电子能谱实验研究

蔡达锋，谷渝秋，郑志坚，周维民，焦春晔

(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）

收稿日期:2013-11-01 修回日期:2014-07-18 出版日期:2014-12-15 发布日期:2014-12-15
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)；四川省教育厅科研资助项目(10ZA012)

Energy distribution of the fast electron from Cu and CH targets irradiated with fs-laser pulses

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

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

Received:2013-11-01 Revised:2014-07-18 Online:2014-12-15 Published:2014-12-15
Supported by:
国家自然科学基金资助项目(10975121)；四川省教育厅科研资助项目(10ZA012)

摘要/Abstract

摘要：

为了研究靶材料对快电子能量分布的影响，采用电子谱仪测量了飞秒激光与Cu和CH靶相互作用中在靶前和靶后产生的快电子能谱。结果显示，在靶前Cu和CH靶的快电子能谱相似，反应了快电子发射对靶材料的依赖性较弱；在靶后Cu和CH靶的快电子能谱具有明显的差异，说明电子的输运过程与靶材料密切相关。冷电子环流以及自生磁场是导致Cu靶快电子能谱“软化”的原因，而对于CH靶麦克斯韦分布的快电子能谱主要由碰撞机制决定。

关键词: 飞秒激光, Cu和CH靶, 快电子, 能谱, 冷电子环流, 自生磁场

Abstract:

In order to investigate the effect of target’s material on fast electron energy distribution, the energy distribution of fast electrons from the front and the rear of Cu and CH targets have been measured during the interaction of femtosecond laser-foil targets. The results show that the fast electron spectrums from the front of Cu and CH targets are similar, which show energy distribution of fast electrons depends very little on material of targets. The fast electron spectrums from the rear of Cu and CH targets are obviously dissimilar, which indicate a mighty effect of target material on fast electron transport. The fast electron spectrums from the Cu target is “soften”, which is due to electron recirculation and self-magnetic field produced by electrons transported in the target. The fast electron spectrums from the CH target is a Maxwellian distribution, which is due to collision effect when electrons transport in the target.

Key words: Femtosecond laser, Cu and CH targets, Fast electron, Energy spectrum, Electron recirculation, Self-magnetic field

中图分类号:

O434.12

蔡达锋，谷渝秋，郑志坚，周维民，焦春晔. 飞秒激光与Cu靶和CH靶相互作用产生的快电子能谱实验研究[J]. 核聚变与等离子体物理, 2014, 34(4): 307-313.

CAI Da-feng,GU Yu-qiu,ZHENG Zhi-jian, ZHOU Wei-min, JIAO Chun-ye. Energy distribution of the fast electron from Cu and CH targets irradiated with fs-laser pulses[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2014, 34(4): 307-313.

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