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arXiv · 2010.05702

Simultaneous measurements on the electron and X-ray spectra from laser-irradiated near-critical-density double-layer targets at relativistic intensity

Jianbo Liu·Pengjie Wang·Yinren Shou·Zhusong Mei·Zhengxuan Cao·Zhuo Pan·Defeng·Kong·Shirui Xu·Guijun Qi·Zhipeng Liu·Shiyou Chen·Jiarui Zhao·Yanying Zhao·Wenjun Ma
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Abstract

We report the experimental results of simultaneous measurements on the electron and X-ray spectra from near-critical-density (NCD) double-layer targets irradiated by relativistic femtosecond pulses at the intensity of 5E19 W/cm^2. The dependence of the electron and X-ray spectra on the density and thickness of the NCD layer was studied. For the optimal targets, electrons with temperature of 5.5 MeV and X-rays with critical energy of 5 keV were obtained. 2D particle-in-cell simulations based on the experimental parameters confirm the electrons are accelerated in the plasma channel through direct laser acceleration, resulting in temperature significantly higher than the pondermotive temperature. Bright X-rays are generated from betatron emission and Thomson backscattering before the electrons leave the double-layer targets.

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Jianbo Liu, Pengjie Wang, Yinren Shou, Zhusong Mei, Zhengxuan Cao, Zhuo Pan, Defeng, Kong, Shirui Xu, Guijun Qi, Zhipeng Liu, Shiyou Chen, Jiarui Zhao, Yanying Zhao, Wenjun Ma. 2020-10-12. Simultaneous measurements on the electron and X-ray spectra from laser-irradiated near-critical-density double-layer targets at relativistic intensity. https://arxiv.org/abs/2010.05702

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