Femtosecond Synchronisation for Externally-Injected Laser Wakefield Acceleration at CLARA

LWFA在证明电子的高梯度和高能量加速方面取得了巨大的成功，最近在20厘米内达到了8 GeV。然而，这些源的发射到发射的能量稳定性和带宽仍然低于传统的加速器;这是由于粒子被“自注入”到激光韦克菲尔德中的固有的非线性和噪声性质。本项目的目标是在美国国家实验室A型电子加速器上实现外注入激光韦克菲尔德场加速的实际演示（STFC达雷斯伯里实验室），通过评估和测量具有飞秒分辨率的激光-电子束同步。能够以如此高的分辨率直接解决电子-激光同步的诊断在技术上具有挑战性，并且不能立即商业化;该项目的一个关键要素将是设计，建造和评估该诊断的操作。激光-电子束同步的幅度将在很大程度上取决于高能激光器中的噪声源。该项目将寻求量化（并在可能的情况下，解决）高能量钛：蓝宝石主振荡器/功率放大器激光系统中的噪声和漂移源，该系统可在激光实验室邻近的COSTA加速器中使用。

LWFA has been hugely successful in demonstrating high gradient and high energy acceleration of electrons, recently up to 8GeV in 20cm. The shot-to-shot energy stability and bandwidth of these sources remains however below that of conventional accelerators; this is due to the intrinsically nonlinear and noisy nature by which particles are 'self-injected' into the laser wakefield. One attractive method to improve the performance of LWFA would be to inject high quality bunches from a conventional accelerator into a LWFA, which would allow energy gain in a linear regime and preserves the injected bunch quality.This project is aimed towards a practical demonstration of externally-injected laser wakefield acceleration at the CLARA electron accelerator facility (STFC Daresbury Laboratory), by evaluating and measuring laser-electron beam synchronization with femtosecond resolution. A diagnostic capable of resolving the electron-laser synchronization directly with such high resolution is technologically challenging and not immediately available commercially; a key element of this project will be to design, build and evaluate the operation of this diagnostic. The magnitude of the laser-electron beam synchronization will be heavily dependent on sources of noise in the high energy laser. The project will seek to quantify (and where possible, resolve) sources of noise and drift in a high energy Ti:Sapphire master oscillator / power amplifier laser system, available in the laser laboratory adjacent to the CLARA accelerator.