由高度相对论性超紧凑电子束实现相干增强的切伦科夫辐射
Coherently Enhanced Cherenkov Radiation by Highly Relativistic and Ultra-Compact Electron Beams
AI总结：
该研究利用等离子体加速器产生的高度相对论性超紧凑电子束，在折射率近1的气体靶中实现了光学及近紫外波段的相干增强切伦科夫辐射，并探究了光谱对束流形状的依赖关系。
AI中文摘要：
切伦科夫辐射是带电粒子以高于介质中光速的速度穿透介质时产生的辐射。近期等离子体加速器研究的进展可产生飞秒级长度、数十微米半径、能量高达数GeV的高度相对论性电子束。本文研究此类极端电子束穿透折射率极接近1的气体靶时产生的切伦科夫辐射，证明由于束流的高能量和高密度，切伦科夫辐射可在光学甚至近紫外波段实现相干增强，还探究了相干增强的切伦科夫辐射光谱对束流形状的依赖关系。
英文摘要：
Cherenkov radiation is emitted when charged particles penetrate dielectric media with velocity higher than the speed of light in the medium. Recent developments in plasma-based accelerator research enable creation of highly relativistic electron beams with femtosecond length and tens of micrometer scale radii, at energies of up to several GeV. Here, we consider Cherenkov radiation emitted by such extreme beams penetrating a gas target with refractive index very close to one. We demonstrate coherent enhancement in the emitted Cherenkov radiation up to the optical or even near-ultraviolet regime, which is due to the high beam energy and density. We also explore the dependence of the coherently enhanced Cherenkov radiation spectrum on the beam shape.
