强激光驱动等离子体空泡中电子的注入和加速的研究

Laser wakefield accelerators are advantageous to the miniaturization of particle accelerators, therefore have important values in the areas of high-energy particle acceleration, free-electron laser, fusion physics, and industrial and medical applications. Plasma bubble (blowout) is a special wakefield driven by an ultrashort ultraintense laser pulse. The bubble regime is acknowledged as one of the most effective laser-driven electron acceleration regimes. The electron injection and acceleration methods are two key issues. Producing high-quality (high-energy, low-energy spread, high-current and low-emittance) electron beams and increasing energy gain in single stage are two important aims..This program is planed to carry out theoretical and simulation studies on electron injection and acceleration methods in bubble regime. This includes studies on dense-plasma ring injection method, exploring controllable injection methods to get high-current and low-emittance electron beams. The new physical laws and optimized acceleration methods of electron acceleration by bubble in plasma channels, especially in dense-plasma tubes, will also be studied. On the basis above, the methods for producing GeV level high-quality electron beams, which may be used as the injection sources of X-ray free-electron lasers, and the methods for increasing energy gain in a single stage and the relevant scaling laws will be studied. This program may provide some relevant theoretical instruction to laser-driven plasma-based electron acceleration experiments.

激光等离子体尾场加速器有利于粒子加速器的小型化，从而在高能粒子加速、自由电子激光、聚变物理和工业医学应用等领域有重要的价值。等离子体空泡是超短超强激光脉冲驱动的特殊尾场。空泡机制是公认的最有效的激光驱动电子加速机制之一，电子注入和加速方法是其中的两个关键问题，获得高品质(高能量、低能散、大电流和低发射度)电子束和提高单次加速的能量增益是两个重要的目标。.本项目拟从理论分析和数值模拟上研究空泡电子加速中的注入和加速方法。包括研究高密等离子体环注入方法，探索可控的、得到大电流和低发射度电子束的注入方法；并研究等离子体通道，特别是高密等离子体管中空泡电子加速新的物理规律和优化加速的方案；在此基础上研究产生GeV量级高品质电子束，以用于X射线自由电子激光的注入源，并探索提高单次加速能量增益的方法及其标度率。本项目将对激光驱动等离子体电子加速实验研究提供一些相关的理论指导。

激光等离子体尾场加速器有利于粒子加速器的小型化，从而在高能粒子加速、自由电子激光、聚变物理和工业医学应用等领域有重要的价值。空泡机制是公认的最有效的激光驱动电子加速机制之一，电子注入和加速方法是其中的两个关键问题。本项目研究表明，在空泡横向边缘附近放置高密度等离子体块或环，可以触发电子注入，控制电子注入位置和增加注入电子数目；收缩的高密等离子体管可以实现收缩的空泡尾场，在一定程度上克服电子加速失相，从而可以提高电子加速能量一倍以上。本项目研究将对激光驱动等离子体电子加速实验研究提供一些有用的理论指导。