Laser-based selective preionization of plasma wakefield accelerator stages

基于激光的等离子体尾场加速器级选择性预电离

• 批准号: 2277943
• 金额: --
• 依托单位: University of Strathclyde
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2277943
• 关键词: Laser; based; selective; preionization; plasma

Particle beam-driven plasma wakefield acceleration (PWFA) is an area of strongly increasing interest in the world-wide accelerator community. Next to large accelerator centres such as SLAC, laser-plasma accelerators such as at the SCAPA centre at University of Strathclyde or the CALA centre at LMU Munich can also engage, by using electron beams from laser-plasma-accelerators (LWFA) as drivers for the PWFA stage [1,2,3]. Generation of wide preionized plasma channels as medium for PWFA is a key task for production of electron beams with high energies and high-quality [4,5]. A further key feature is to ionize only one component in a multi-component gas-plasma, such that an ionized component is available for realization of plasma photocathodes. These are based on the feature that electron-driven plasma wakefield acceleration does not require excessive peak electric driver fields to excite strong plasma waves, due to its unipolar electric drive beam field distribution. The peak electric field of electron beams required capable to excite such waves is many orders of magnitude lower than those of high power laser pulses due to their oscillating electric field structure. This feature allows to decouple wake excitation from electron bunch injection by exploiting species of significantly different tunnelling ionization thresholds such as hydrogen and helium. A laser pulse with peak electric fields locally exceeding that of the high ionization threshold medium can therefore be exploited to release and inject electrons in a controlled way at arbitrary spatiotemporal positions. The chief attraction of this is that plasma cathodes can be realized which allow controlled and highly tunable injection of electron populations with extremely low so-called electron beam emittance and therefore ultrahigh brightness, many orders of magnitude better than state-of-the-art. Such capabilities may be transformative for coherent and incoherent photon science sources, high field and high energy physics. In turn, this means that selective ionization of the low ionization threshold component and the high ionization threshold component is required. This includes preionization of the low ionization threshold component uniformly in a wide and long region, shaping of plasma upramps and downramps, as well as locally very confined ionization of the higher ionization threshold component for plasma photocathode injection. This is the core R&D theme of this PhD and implies two main objectives: - Selective laser-based preionization of low-ionization threshold media such as hydrogen. The aim here is an up to metre-long plasma channel with width up to a millimetre, without hot spots which would ionize relevant higher ionization threshold media - Laser-based localized tunneling ionization of high-ionization threshold media such as helium- Metrology of incoming electron and laser pulses, plasma medium and produced electron pulsesThe project is realized in a European collaboration with LMU as main partner. [1] Hidding, B. .. Karsch, S. et al., Monoenergetic Energy Doubling in a Hybrid Laser-Plasma Wakefield Accelerator, Phys. Rev. Lett. 104, 195002 (2010)[2] Direct observation of plasma waves and dynamics induced by laser-accelerated electron beams, M. F. Gilljohann .. B. Hidding .. S. Karsch, Physical Review X 9, 011046 (2019)[3] T. Kurz, T. Heinemann et al., Demonstration of a compact plasma accelerator powered by laser-accelerated electron beams, arXiv:1909.06676[4] G.G. Manahan .. Hidding, B., Single-stage plasma-based correlated energy spread compensation for ultrahigh 6D brightness electron beams, Nat. Communications 8, 15705 (2017)[5] A. Deng .. Hidding, B., Electron bunch generation from a plasma photocathode, Nat. Physics (2019)

粒子梁驱动的等离子体韦克场加速度（PWFA）是一个对全球加速器社区兴趣不大的领域。在大型加速器中心（例如SLAC），例如在Strathclyde大学的Scapa Center或LMU慕尼黑的Cala Center等大型加速器中心，也可以通过使用Laser-Plasma-Accelerators（LWFA）的电子束作为PWFA阶段的驱动程序来参与。将广泛的预先化血浆通道作为PWFA的培养基是生产具有高能量和高质量的电子束的关键任务[4,5]。另一个关键特征是仅在多组分气值中将一个组件电离，以便可用于实现等离子光（等离子体光电座）。这些基于以下特征：电子驱动的等离子体Wakefield加速度不需要过多的峰值电驱动器场，即可激发强力等离子体波，因为其单极电动驱动器梁场分布。由于其振荡电场结构，其峰值的电子梁的峰值电场比高功率激光脉冲的峰值低许多数量级。此功能可以通过利用明显不同的隧道电离电离阈值（例如氢和氦）的物种来解除电子束注射的唤醒激发。因此，具有局部峰值电场的激光脉冲可以利用高电离阈值培养基的激光脉冲，以在任意时空位置以受控方式释放和注入电子。这样的主要吸引力是可以实现血浆阴极，该血浆允许对具有极低的所谓电子束发射的电子种群进行控制，高度可调的电子种群，因此超高亮度，许多数量级比最终的数量级好。这种能力可能是针对连贯和不连贯的光子科学，高场和高能量物理学的变革性的。反过来，这意味着需要低电离阈值组件和高电离阈值组件的选择性电离。这包括在宽且长的区域均匀地统一地对低电离阈值组件进行预离子化，血浆上升剂和倾斜的形状，以及局部非常密封的等离子化阈值分量的电离。这是该博士学位的核心R＆D主题，暗示了两个主要目标： - 基于选择性激光的低离子化阈值介质（例如氢）的预离子。 The aim here is an up to metre-long plasma channel with width up to a millimetre, without hot spots which would ionize relevant higher ionization threshold media - Laser-based localized tunneling ionization of high-ionization threshold media such as helium- Metrology of incoming electron and laser pulses, plasma medium and produced electron pulsesThe project is realized in a European collaboration with LMU as main 伙伴。 [1] Hidding，B. .. Karsch，S。等人，在混合激光 - 播种器韦克菲尔德加速器中，单烯能量加倍，物理。莱特牧师。 104，195002（2010）[2]直接观察激光加速的电子束引起的血浆波和动力学，M。F. Gilljohann .. B. Hidding .. S. Karsch .. S. Karsch，物理审查X 9，011046（2019）[3] T. Kurz，T。Kurz，T。Heinemann et accaste complase-accmane compacter-las compacter compter compacter compacter compter compacter compter compter compacter compter in。电子梁，ARXIV：1909.06676 [4] G.G. Manahan .. Hidding，B。，基于单阶段的基于等离子体的相关能量扩散补偿超高6D亮度电子束，NAT。通信8，15705（2017）[5] A. Deng .. Hidding，B。，来自等离子体光电极的电子束生成，Nat。物理学（2019年）