Staged Acceleration of Plasma Accelerators

激光韦克菲尔德加速器（LWFA）的大加速场可以使到达高能所需的距离减少许多数量级。更高的激光功率和改进的靶向技术增加了能量记录，目前最高可达7.8GeV。在单级中达到更高的能量需要进一步增加激光功率和进一步降低等离子体密度，从而导致更弱的加速梯度。为了保持更高的平均加速梯度，已经提出了使用多级，并且已经在100 MeV水平上进行了验证。然而，在保持电子束质量的同时耦合驱动激光器仍然是一个巨大的挑战，并且如果要在多个级上实现高平均加速梯度，则必须复杂地克服这个挑战。在这个项目中，我们将研究使用高强度的紧凑加速结构（等离子体镜）将激光束耦合到多个LWFA级中，以便能够在高能量下产生高质量的电子束。

The large accelerating fields of laser wakefield accelerators (LWFA) can reduce the distance required to reach high energies by many orders of magnitude. Higher laser power and improved targetry has increase the energy record, up to a current maximum of 7.8GeV. Reaching much higher energies in a single stage requires further increases in the laser power and further reductions in the plasma density, resulting in weaker accelerating gradients. To maintain a higher average acceleration gradient , the use of multiple stages has been proposed, and has been demonstrated at the 100 MeV level. However, coupling of the drive laser while maintaining electron beam quality remains a huge challenge, and one that must be overcome compactly if a high average accelerating gradient is to be achieved across multiple stages. In this project we will investigate the use of compact accelerating structures (plasma mirrors) at high intensity to couple laser beams into multiple LWFA stages, with a view to enabling high quality electron beams to be generated at high energy.