论文标题
由PW次秒激光产生的重离子束的特性
Properties of heavy ion beams produced by a PW sub-picosecond laser
论文作者
论文摘要
本文报告了数值研究结果，该结果是从高能量（60 J）高强度（〜2 x 10^20 W/cm2）子PS激光脉冲辐射的亚微米金靶中产生重离子的结果。使用多维（2D3V）粒子粒子代码研究了由0.5-UM金靶产生的重离子束的性质。已经发现，在纯（没有污染物）靶标的情况下，离子束包含20多个离子物种，电荷> 30，高能量（> 20 MeV）离子的总数达到远高于10^12。离子能谱宽，最大能量> 1 GEV，平均能量> 100 MEV。在距离目标〜1毫米的距离处，离子束的强度为〜10^15 w/cm2，离子通量达到〜10^16离子/cm2，离子脉冲持续时间为〜100 ps。污染物显着降低了离子束参数，平均离子能以及由受污染的金目标产生的离子束的强度和通知几乎低的数量级低于纯目标。在纯金目标的情况下，具有与传统的RF驱动加速器几乎无法实现的重离子光束，因此它们可以打开新的研究领域，特别是在高能量密度物理学中。
The paper reports the results of numerical studies on the generation of heavy ions from a sub-micrometre gold target irradiated by a high-energy (60 J) high-intensity (~ 2 x 10^20 W/cm2) sub-ps laser pulse. The properties of the heavy ion beam produced from a 0.5-um gold target with and without hydrogen contaminants are investigated using a multi-dimensional (2D3V) particle-in-cell code. It was found that in the case of the pure (without the contaminants) target, the ion beam contains over 20 ion species with a charge state > 30 and a total number of high-energy (> 20 MeV) ions reaching values well above 10^12. The ion energy spectrum is broad, with maximum energies > 1 GeV and mean energies > 100 MeV. At a distance ~ 1 mm from the target, the intensity of the ion beam is ~ 10^15 W/cm2, the ion fluence reaches ~ 10^16 ions/cm2, and the ion pulse duration is ~ 100 ps. The contaminants significantly reduce the ion beam parameters and both the mean ion energy and the intensity and fluence of the ion beam generated from the contaminated gold target are almost an order of magnitude lower than those produced from the pure target. Heavy ion beams with the parameters obtained in the case of the pure gold target are barely achievable in conventional RF-driven accelerators, so they can open the door to new areas of research, in particular in high energy-density physics.
