From Phase Space Manipulation to First Light from a Laser Plasma Accelerator Powered Free Electron Laser

这个项目的目标是开发一个桌面x射线源。高亮度x射线光源是探测化学、生物和物理系统不可缺少的工具。x射线源是由加速器中产生的电子束驱动的，该加速器依靠非常强的激光束来激发电离气体云中的波，等离子体，电子可以在等离子体上冲浪以达到高能量。这项技术已经表明，与使用传统技术的几个足球场长的加速器相比，电子束可以从只有几英寸长的设备中产生。为了产生大量的x射线，电子束的质量必须非常好，而这个项目将证明这样的电子束实际上是可以产生的。该项目的成功将大大减少x射线源的尺寸，并将该工具带到个人实验室和研究人员，促进科学的进步。该项目还支持三名研究生的教育，他们将接受超短光束物理学、激光等离子体相互作用和先进加速器概念方面的培训。该项目旨在利用激光等离子体加速器（LPA）产生的光束，开发一种紧凑、超快（飞秒）的软x射线辐射源。通过将超短激光等离子体加速电子束耦合到传统的磁波动器中，可以产生强辐射。电子束的传输将通过两个磁透镜进行，其中包括最近开发的超强有源等离子体透镜和一个用于能量色散的减速弯。后者对于减小光束切片能量扩散至关重要，从而能够观测到自由电子激光增益。通过基于波动器的辐射诊断，电子束质量将在每次射击时进行测量，并将提供必要的反馈，以了解和控制对激光等离子体加速器和传输晶格施加的要求，以提供高质量的光束。该项目分为三个阶段：(1)使用新的100tw级激光系统在稳定的高电荷模式下运行LPA。(2)实现并演示了LPA源到波动器传输系统，并调试了嵌入强聚焦的波动器。预计在10-100 eV范围内，每发射10^8个光子的超短非相干波动辐射。(3)通过调整弯道，实现波动辐射的相干增强。这种光源本质上与激光驱动器同步，使这种紧凑的光源成为超快科学中泵浦探针应用的理想选择。

The goal of this project is to develop a table-top x-ray source. High-brightness x-ray light sources are indispensible tools to probe chemical, biological, and physical systems. The x-ray source is driven by electron beams generated in an accelerator that relies on very intense laser beams to excite waves in a cloud of ionized gas, a plasma, on which electrons can surf to reach high energies. This technology has already shown that electron beams can be produced from devices that are only a few inches long compared to several-football-field-long accelerators using conventional technology. In order for a lot of x-rays to be generated, the electron beam quality has to be excellent, and this project will demonstrate that such beams can, in fact, be produced. Success of this project will greatly reduce the size of x-ray sources and bring this tool to individual laboratories and investigators, promoting the advancement of science. This project also supports the education of three graduate students, to be trained in the physics of ultra-short beams, laser-plasma interactions, and advanced accelerator concepts.The project aims at developing a compact, ultra-fast (femtosecond), soft X-ray radiation source using beams produced by a laser-plasma accelerator (LPA). Intense radiation can be generated via the undulator radiation mechanism by coupling the ultra-short laser-plasma-accelerated electron beam into a conventional magnetic undulator. Transport of the electron beams will be performed with two magnetic lenses, incorporating recently-developed ultra-strong active plasma lenses, and a chicane for energy dispersion. The latter is critical to reduce the beam slice energy spread, enabling the observation of free-electron laser gain. By fielding undulator-based radiation diagnostics, the electron beam quality will be measured on every shot and will provide the necessary feedback to understand and control the requirements imposed on the laser plasma accelerator and transport lattice to deliver high quality beams. The project consists of three phases: (1) Operate the LPA in a stable and high-charge mode with the new 100-TW-class laser system. (2) Implement and demonstrate the LPA source-to-undulator transport system, and commission an undulator embedded with strong focusing. Ultra-short incoherent undulator radiation with on the order of 10^8 photons per shot in the 10-100 eV range is expected. (3) By tuning the chicane, coherent enhancement of the undulator radiation will be pursued. This light source is intrinsically synchronized to the laser driver, making such a compact source ideal for pump-probe applications in ultrafast science.