An electron plasma lens is a cost-effective, compact, strong-focusing element that can ensure efficient capture of low-energy proton and ion beams from laser-driven sources. A Gabor lens prototype was built for high electron density operation at Imperial College London. The parameters of the stable operation regime of the lens and its performance during a beam test with 1.4 MeV protons are reported here. Narrow pencil beams were imaged on a scintillator screen 67 cm downstream of the lens. The lens converted the pencil beams into rings that show position-dependent shape and intensity modulation that are dependent on the settings of the lens. Characterisation of the focusing effect suggests that the plasma column exhibited an off-axis rotation similar to the $m=1$ diocotron instability. The association of the instability with the cause of the rings was investigated using particle tracking simulations.

中文翻译：

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通过Gabor（等离子）透镜原型的异常光束传输

电子等离子透镜是一种经济高效的紧凑型强聚焦元件，可确保有效捕获激光驱动源发出的低能质子和离子束。Gabor镜头原型是在伦敦帝国学院为高电子密度操作而制造的。此处报道了在1.4 MeV质子的束测试中，镜片稳定工作状态的参数及其性能。狭窄的笔形光束在镜头下游67厘米的闪烁屏上成像。镜头将笔形光束转换成环，这些环显示出与位置有关的形状和强度调制，这些形状和强度调制取决于镜头的设置。聚焦效应的表征表明，等离子柱表现出的轴外旋转类似于$米=\mathrm{1个}$电子整流子的不稳定性。使用粒子跟踪模拟研究了不稳定性与产生环的原因之间的关系。